COP8ACC Family
8-Bit CMOS ROM Based and OTP Microcontrollers with
4k or 16k Memory and High Resolution A/D
General Description
The COP8ACC Family ROM based microcontrollers are
highly integrated COP8™Feature core devices with 4k
memory and advanced features including a High-Resolution
A/D. These single-chip CMOS devices are suited for applica-
tions requiring a full featured, low EMI controller with an A/D
(only one external capacitor required). COP8ACC7 devices
are pin and software compatible (different V
CC
range) 16k
OTP EPROM versions for pre-production. Erasable win-
dowed versions are available for use with a range of COP8
software and hardware development tools.
Family features include an 8-bit memory mapped architec-
ture, 4 MHz CKI with 2.5µs instruction cycle, 6 channel A/D
with 12-bit resolution, analog capture timer, analog current
source and V
CC
/2 reference, one multi-function 16-bit timer/
counter, MICROWIRE/PLUS serial I/O, two power saving
HALT/IDLE modes, MIWU, high current outputs, software
selectable I/O options, WATCHDOG™timer and Clock Moni-
tor, Low EMI 2.5V to 5.5V operation and 20/28 pin packages.
Devices included in this datasheet are:
Device Memory (bytes) RAM (bytes) I/O Pins Packages Temperature
COP8ACC5xxx9 4k ROM 128 15/23 20 SOIC, 28 DIP/SOIC 0 to +70˚C
COP8ACC5xxx8 4k ROM 128 15/23 20 SOIC, 28 DIP/SOIC -40 to +85˚C
COP8ACC7xxx9 16k OTP EPROM 128 15/23 20 SOIC, 28 DIP/SOIC 0 to +70˚C
COP8ACC7xxx8 16k OTP EPROM 128 15/23 20 SOIC, 28 DIP/SOIC -40 to +85˚C
Key Features
nAnalog Function Block with 12-bit A/D including
— Analog comparator with seven input mux
— Constant Current Source and V
CC/2
Reference
— 16-bit capture timer (upcounter) clocked from CKI
with auto reset on timer startup
nQuiet design (reduced radiated emissions)
n4096 bytes on-board ROM or 16,384 OTP EPROM with
security feature
n128 bytes on-board RAM
Additional Peripheral Features
nIdle Timer
nOne 16-bit timer with two 16-bit registers supporting:
— Processor Independent PWM mode
— External Event counter mode
— Input Capture mode
nMulti-Input Wake-Up (MIWU) with optional interrupts
nWATCHDOG and clock monitor logic
nMICROWIRE/PLUS™serial I/O with programmable shift
clock-polarity
I/O Features
nSoftware selectable I/O options (Push-Pull Output, Weak
Pull-Up Input, High Impedance Input)
nHigh current outputs
nSchmitt Trigger inputs on ports G and L
nPackages: 28 DIP/SO with 23 I/O pins,
20 SO with 15 I/O pins
CPU/Instruction Set Features
n2.5 µs instruction cycle time
nEight multi-source vectored interrupt servicing
— External Interrupt
— Idle Timer T0
— Timer T1 associated Interrupts
— MICROWIRE/PLUS
— Multi-Input Wake Up
— Software Trap
— Default VIS
— A/D (Capture Timer)
n8-bit Stack Pointer (SP)—stack in RAM
nTwo 8-bit Registers Indirect Data Memory Pointers
(B and X)
Fully Static CMOS
nTwo power saving modes: HALT and IDLE
nSingle supply operation: 2.5V to 5.5V for COP8ACC5
nSingle supply operation: 2.7V to 5.5V for COP8ACC7
nTemperature ranges: 0˚C to +70˚C, −40˚C to +85˚C
Development System
nEmulation and OTP devices
nReal time emulation and full program debug offered by
MetaLink development system
Applications
nBattery Chargers
nAppliances
COP8™, MICROWIRE™, MICROWIRE/PLUS™, and WATCHDOG™are trademarks of National Semiconductor Corporation.
TRI-STATE®is a registered trademark of National Semiconductor Corporation.
iceMASTER®is a registered trademark of MetaLink Corporation.
July 2000
COP8ACC Family 8-Bit CMOS ROM Based and OTP Microcontrollers with
4k or 16k Memory and High Resolution A/D
© 2000 National Semiconductor Corporation DS012865 www.national.com
Applications (Continued) nData Acquisition systems
Block Diagram
Connection Diagrams
DS012865-1
FIGURE 1. Block Diagram
DS012865-2
Top View
Order Number COP8ACC528N9 or COP8ACC528N8
See NS Molded Package Number N28A
Order Number COP8ACC528M9 or COP8ACC528M8
Order Number COP8ACC728N9-XE or
COP8ACC728N8-XE
Order Number COP8ACC728M9-XE or
COP8ACC728M8-XE
See NS Molded Package Number M28B
DS012865-3
Note: -X Crystal Oscillator
Note: -E Halt Enable
Top View
Order Number COP8ACC520M9 or COP8ACC520N8
Order Number COP8ACC720M9-XE or
COP8ACC720N8-XE
See NS Molded Package Number M20B
FIGURE 2. Connection Diagrams
COP8ACC Family
www.national.com 2
Connection Diagrams (Continued)
Pinouts for 28-Pin, 20-Pin Packages
Port Type Alt. Fun Alt. Fun 28-Pin 20-Pin
DIP/SO SO
L4 I/O MIWU Ext. Int. 4
L5 I/O MIWU Ext. Int. 5
L6 I/O MIWU Ext. Int. 6
L7 I/O MIWU Ext. Int. 7
G0 I/O INT 23 15
G1 WDOUT 24 16
G2 I/O T1B 25 17
G3 I/O T1A 26 18
G4 I/O SO 27 19
G5 I/O SK 28 20
G6 I SI 1 1
G7 I/CKO HALT Restart 2 2
D0 O 11 7
D1 O 12 8
D2 O 13 9
D3 O 14
I0 I Analog CH1 15 10
I1 I I
SRC
16 11
I2 I Analog CH2 17 12
I3 I Analog CH3 18 13
I4 I Analog CH4 19 14
I5 I Analog CH5 20
I6 I Analog CH6 21
I7 I C
OUT
22
V
CC
95
GND 8 4
CKI 3 3
RESET 10 6
Ordering Inforamtion
DS012865-38
FIGURE 3. Part Numbering Scheme
COP8ACC Family
www.national.com3
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage (V
CC
)7V
Voltage at Any Pin −0.3V to V
CC
+0.3V
Total Current into V
CC
Pin (Source) 100 mA
Total Current out of GND Pin (Sink) 110 mA
Storage Temperature Range −65˚C to +140˚C
Note 1: Absolute maximum ratings indicate limits beyond which damage to
the device may occur. DC and AC electrical specifications are not ensured
when operating the device at absolute maximum ratings.
DC Electrical Characteristics
0˚C ≤T
A
≤+70˚C unless otherwise specified [OTP Value]
Parameter Conditions Min Typ Max Units
Operating Voltage Peak-to-Peak 2.5 [2.7] 5.5 V
Power Supply Ripple (Note 2) 0.1 V
CC
V
Supply Current (Note 3)
CKI = 4 MHz V
CC
= 5.5V, t
C
= 2.5 µs 5.5 [9.5] mA
CKI = 4 MHz V
CC
= 4V, t
C
= 2.5 µs 2.5 [6.5] mA
CKI = 1 MHz V
CC
= 4V, t
C
= 10 µs 1.4 [5.4] mA
HALT Current (Note 4) V
CC
= 5.5V, CKI=0MHz <5 8 [10] µA
V
CC
= 4V, CKI = 0 MHz <3 4 [6] µA
IDLE Current
CKI = 4 MHz V
CC
= 5.5V, t
C
= 2.5 µs 1.5 mA
CKI = 1 MHz V
CC
= 4V, t
C
= 10 µs 0.5 mA
Input Levels (V
IH
,V
IL
)
RESET
Logic High 0.8 V
CC
V
Logic Low 0.2 V
CC
V
CKI, All Other Inputs
Logic High 0.7 V
CC
V
Logic Low 0.2 V
CC
V
Hi-Z Input Leakage V
CC
= 5.5V 1 1 µA
Input Pullup Current V
CC
= 5.5V, V
IN
= 0V −40 −250 µA
G and L Port Input Hysteresis (Note 6) 0.35 V
CC
V
Output Current Levels
D Outputs
Source V
CC
= 4V, V
OH
= 3.3V −0.4 mA
V
CC
= 2.5V [2.7V], V
OH
= 1.8V −0.2 mA
Sink V
CC
= 4V, V
OL
=1V 10 mA
V
CC
= 2.5V [2.7V], V
OL
= 0.4V 2.0 mA
All Others
Source (Weak Pull-Up Mode) V
CC
= 4V, V
OH
= 2.7V −10 −110 µA
V
CC
= 2.5V [2.7V], V
OH
= 1.8V −2.5 −33 µA
Source (Push-Pull Mode) V
CC
= 4V, V
OH
= 3.3V −0.4 mA
V
CC
= 2.5V [2.7V], V
OH
= 1.8V −0.2 mA
Sink (Push-Pull Mode) V
CC
= 4V, V
OL
= 0.4V 1.6 mA
V
CC
= 2.5V [2.7V], V
OL
= 0.4V 0.7 mA
TRI-STATE®Leakage V
CC
= 5.5V 1 1 µA
Allowable Sink/Source
Current per Pin
D Outputs (Sink) 15 mA
All others 3mA
Maximum Input Current Room Temp ±200 mA
without Latchup (Note 5)
RAM Retention Voltage, V
r
500 ns Rise and Fall Time (min) 2 V
COP8ACC Family
www.national.com 4
DC Electrical Characteristics (Continued)
0˚C ≤T
A
≤+70˚C unless otherwise specified [OTP Value]
Parameter Conditions Min Typ Max Units
Input Capacitance (Note 6) 7 pF
Load Capacitance on D2 (Note 6) 1000 pF
AC Electrical Characteristics
0˚C ≤T
A
≤+70˚C unless otherwise specified [OTP Value]
Parameter Conditions Min Typ Max Units
Instruction Cycle Time (t
C
)
Crystal, Resonator 2.5V, [2.7V] ≤V
CC
≤4V 2.5 DC µs
4V ≤V
CC
≤5.5V 1.0 DC µs
R/C Oscillator 2.5V, [2.7V] ≤V
CC
≤4V 7.5 DC µs
4V ≤V
CC
≤5.5V 3.0 DC µs
Inputs
t
SETUP
4V ≤V
CC
≤5.5V 200 ns
2.5V, [2.7V] ≤V
CC
≤4V 500 ns
t
HOLD
4V ≤V
CC
≤5.5V 60 ns
2.5V, [2.7V] ≤V
CC
≤4V 150 ns
Output Propagation Delay (Note 6) R
L
= 2.2k, C
L
= 100 pF
t
PD1
,t
PD0
SO, SK 4V ≤V
CC
≤5.5V 0.7 µs
2.5V, [2.7V] ≤V
CC
≤4V 1.75 µs
All Others 4V ≤V
CC
≤5.5V 1 µs
2.5V, [2.7V] ≤V
CC
≤4V 2.5 µs
MICROWIRE™Setup Time (t
UWS
) (Note
6) V
CC
≥4V 20 ns
MICROWIRE Hold Time (t
UWH
) (Note 6) V
CC
≥4V 56 ns
MICROWIRE Output Propagation Delay
(t
UPD
)V
CC
≥4V 220 ns
Input Pulse Width (Note 7)
Interrupt Input High Time 1 t
C
Interrupt Input Low Time 1 t
C
Timer 1, 2, 3 Input High Time 1 t
C
Timer 1, 2, 3 Input Low Time 1 t
C
Reset Pulse Width 1 µs
Note 2: Maximum rate of voltage change must be <0.5V/ms.
Note 3: Supply current is measured after running 2000 cycles with a square wave CKI input, CKO open, inputs at rails and outputs open.
Note 4: The HALT mode will stop CKI from oscillating in the RC and the Crystal configurations. Measurement of IDD HALT is done with device neither sourcing or
sinking current; with L, C, and G0–G5 programmed as low outputs and not driving a load; all outputs programmed low and not driving a load; all inputs tied to VCC;
clock monitor and comparator disabled. Parameter refers to HALT mode entered via setting bit 7 of the G Port data register. Part will pull up CKI during HALT in crystal
clock mode.
Note 5: Pins G6 and RESET are designed with a high voltage input network. These pins allow input voltages VCC and the pins will have sink current to VCC when
biased at voltages VCC (the pins do not have source current when biased at a voltage below VCC). The effective resistance to VCC is 750Ω(typical). These two pins
will not latch up. The voltage at the pins must be limited to less than 14V. WARNING: Voltages in excess of 14V will cause damage to the pins. This warning
excludes ESD transients.
Note 6: The output propagation delay is referenced to the end of the instruction cycle where the output change occurs.
Note 7: Parameter characterized but not tested.
Note 8: tC= Instruction Cycle Time.
COP8ACC Family
www.national.com5
Absolute Maximum Ratings (Note 9)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage (V
CC
)7V
Voltage at Any Pin −0.3V to V
CC
+0.3V
Total Current into V
CC
Pin (Source) 100 mA
Total Current out of GND Pin (Sink) 110 mA
Storage Temperature Range −65˚C to +140˚C
Note 9: Absolute maximum ratings indicate limits beyond which damage to
the device may occur. DC and AC electrical specifications are not ensured
when operating the device at absolute maximum ratings.
DC Electrical Characteristics
−40˚C ≤T
A
≤+85˚C unless otherwise specified [OTP Value]
Parameter Conditions Min Typ Max Units
Operating Voltage 2.5 [2.7] 5.5 V
Power Supply Ripple (Note 10) Peak-to-Peak 0.1 V
CC
V
Supply Current (Note 11)
CKI = 4 MHz V
CC
= 5.5V, t
C
= 2.5 µs 5.5 [9.5] mA
CKI = 4 MHz V
CC
= 4V, t
C
= 2.5 µs 2.5 [6.5] mA
CKI = 1 MHz V
CC
= 4V, t
C
= 10 µs 1.4 [5.4] mA
HALT Current (Note 12) V
CC
= 5.5V, CKI=0MHz <5 10 [12] µA
V
CC
= 4V, CKI = 0 MHz <3 6 [8] µA
IDLE Current
CKI = 4 MHz V
CC
= 5.5V, t
C
= 2.5 µs 1.5 mA
CKI = 1 MHz V
CC
= 4V, t
C
= 10 µs 0.5 mA
Input Levels (V
IH
,V
IL
)
RESET
Logic High 0.8 V
CC
V
Logic Low 0.2 V
CC
V
CKI, All Other Inputs
Logic High 0.7 V
CC
V
Logic Low 0.2 V
CC
V
Hi-Z Input Leakage V
CC
= 5.5V −2 +2 µA
Input Pullup Current V
CC
= 5.5V, V
IN
= 0V −40 −250 µA
G and L Port Input Hysteresis (Note 14) 0.35 V
CC
V
Output Current Levels
D Outputs
Source V
CC
= 4V, V
OH
= 3.3V −0.4 mA
V
CC
= 2.5V [2.7V], V
OH
= 1.8V −0.2 mA
Sink V
CC
= 4V, V
OL
=1V 10 mA
V
CC
= 2.5V [2.7V], V
OL
= 0.4V 2.0 mA
All Others
Source (Weak Pull-Up Mode) V
CC
= 4V, V
OH
= 2.7V −10 −110 µA
V
CC
= 2.5V [2.7V], V
OH
= 1.8V −2.5 −33 µA
Source (Push-Pull Mode) V
CC
= 4V, V
OH
= 3.3V −0.4 mA
V
CC
= 2.5V [2.7V], V
OH
= 1.8V −0.2 mA
Sink (Push-Pull Mode) V
CC
= 4V, V
OL
= 0.4V 1.6 mA
V
CC
= 2.5V [2.7V], V
OL
= 0.4V 0.7 mA
TRI-STATE Leakage V
CC
= 5.5V −2 +2 µA
Allowable Sink/Source
Current per Pin
D Outputs (Sink) 15 mA
All others 3mA
Maximum Input Current Room Temp ±200 mA
without Latchup (Note 13)
RAM Retention Voltage, V
r
500 ns Rise and Fall Time (min) 2 V
COP8ACC Family
www.national.com 6
DC Electrical Characteristics (Continued)
−40˚C ≤T
A
≤+85˚C unless otherwise specified [OTP Value]
Parameter Conditions Min Typ Max Units
Input Capacitance (Note 14) 7 pF
Load Capacitance on D2 (Note 14) 1000 pF
AC Electrical Characteristics
−40˚C ≤T
A
≤+85˚C unless otherwise specified [OTP Value]
Parameter Conditions Min Typ Max Units
Instruction Cycle Time (t
C
)
Crystal, Resonator 2.5V, [2.7V] ≤V
CC
<4V 2.5 DC µs
4V ≤V
CC
≤5.5V 1.0 DC µs
R/C Oscillator 2.5V, [2.7V] ≤V
CC
<4V 7.5 DC µs
4V ≤V
CC
<5.5V 3.0 DC µs
Inputs
t
SETUP
4V ≤V
CC
≤5.5V 200 ns
2.5V, [2.7V] ≤V
CC
<4V 500 ns
t
HOLD
4V ≤V
CC
≤5.5V 60 ns
2.5V, [2.7V] ≤V
CC
<4V 150 ns
Output Propagation Delay (Note 14) R
L
= 2.2k, C
L
= 100 pF
t
PD1
,t
PD0
SO, SK 4V ≤V
CC
≤5.5V 0.7 µs
2.5V, [2.7V] ≤V
CC
<4V 1.75 µs
All Others 4V ≤V
CC
≤5.5V 1 µs
2.5V, [2.7V] ≤V
CC
<4V 2.5 µs
MICROWIRE Setup Time (t
UWS
) (Note 14) V
CC
≥4V 20 ns
MICROWIRE Hold Time (t
UWH
) (Note 14) V
CC
≥4V 56 ns
MICROWIRE Output Propagation Delay (t
UPD
)V
CC
≥4V 220 ns
Input Pulse Width (Note 15)
Interrupt Input High Time 1 t
C
Interrupt Input Low Time 1 t
C
Timer 1, 2, 3 Input High Time 1 t
C
Timer 1, 2, 3 Input Low Time 1 t
C
Reset Pulse Width 1 µs
Note 10: Maximum rate of voltage change must be <0.5 V/ms.
Note 11: Supply current is measured after running 2000 cycles with a square wave CKI input, CKO open, inputs at rails and outputs open.
Note 12: The HALT mode will stop CKI from oscillating in the RC and the Crystal configurations. Measurement of IDD HALT is done with device neither sourcing or
sinking current; with L, C, and G0–G5 programmed as low outputs and not driving a load; all outputs programmed low and not driving a load; all inputs tied to VCC;
clock monitor and comparator disabled. Parameter refers to HALT mode entered via setting bit 7 of the G Port data register. Part will pull up CKI during HALT in crystal
clock mode.
Note 13: Pins G6 and RESET are designed with a high voltage input network. These pins allow input voltages VCC and the pins will have sink current to VCC when
biased at voltages greater than VCC (the pins do not have source current when biased at a voltage below VCC). The effective resistance to VCC is 750Ω(typical).
These two pins will not latch up. The voltage at the pins must be limited to less than 14V. WARNING: Voltages in excess of 14V will cause damage to the pins.
This warning excludes ESD transients.
Note 14: The output propagation delay is referenced to the end of the instruction cycle where the output change occurs.
Note 15: Parameter characterized but not tested.
Note 16: tC= Instruction Cycle Time.
COP8ACC Family
www.national.com7
Comparator AC and DC Characteristics
V
CC
= 5V, −40˚C ≤T
A
≤+85˚C
Parameter Conditions Min Typ Max Units
Input Offset Voltage 0.4V <V
IN
<V
CC
−1.5V 10 25 mV
Input Common Mode Voltage Range (Note
17) 0.4 V
CC
−1.5 V
Voltage Gain 300k V/V
V
CC
/2 Reference 4.0V <V
CC
<5.5V 0.5 V
CC
−0.04 0.5V
CC
0.5V
CC
+0.04 V
DC Supply Current V
CC
= 5.5V 250 µA
For Comparator (when enabled)
DC Supply Current V
CC
= 5.5V 50 80 µA
For V
CC
/2 reference (when enabled)
DC Supply Current V
CC
= 5.5V 200 µA
For Constant Current Source (when enabled)
Constant Current Source 4.0V <V
CC
<5.5V 7 20 32 µA
Current Source Variation 4.0V <V
CC
<5.5V 2 µA
Temp = Constant
Current Source Enable Time 1.5 2 µs
Comparator Response Time 10 mV overdrive, 1 µs
100 pF load
Note 17: The device is capable of operating over a common mode voltage range of 0 to VCC − 1.5V, however increased offset voltage will be observed between 0V
and 0.4V.
DS012865-4
FIGURE 4. MICROWIRE/PLUS Timing
COP8ACC Family
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Typical Performance Characteristics (−55˚C ≤T
A
= +125˚C)
Port D Source Current (COP8ACC5 Only)
DS012865-40
Port D Sink Current (COP8ACC5 Only)
DS012865-41
Ports C/G/L Source Current
DS012865-42
Ports C/G/L Sink Current
DS012865-43
Ports C/G/L Weak Pull-Up Source Current
DS012865-44
Dynamic I
DD
vs V
CC
DS012865-45
COP8ACC Family
www.national.com9
Typical Performance Characteristics (−55˚C ≤T
A
= +125˚C) (Continued)
Idle — I
DD
vs V
CC
(COP8ACC5 Only)
DS012865-46
Halt — I
DD
vs V
CC
(COP8ACC5 Only)
DS012865-47
Current Source Regulation at −55˚C
DS012865-48
Current Source Regulation at 125˚C
DS012865-49
Current Source Regulation at V
CC
= 5.0V
DS012865-50
V
REF
Variation from V
CC
/2
DS012865-51
COP8ACC Family
www.national.com 10
Pin Descriptions
V
CC
and GND are the power supply pins. All V
CC
and GND
pins must be connected.
CKI is the clock input. This can come from an R/C generated
oscillator, or a crystal oscillator (in conjunction with CKO).
See Oscillator Description section.
RESET is the master reset input. See Reset description sec-
tion.
The devices contain two bidirectional (one 8-bit, one 4-bit)
I/O ports (G and L), where each individual bit may be inde-
pendently configured as a weak pullup input, TRI-STATE®
(Hi-Z) input or push pull output under program control. Ports
G- and L- feature Schmitt trigger inputs. Three data memory
address locations are allocated for each of these I/O ports.
Each I/O port has two associated 8-bit memory mapped reg-
isters, the CONFIGURATION register and the output DATA
register. A memory mapped address is also reserved for the
input pins of each I/O port. (See the memory map for the
various addresses associated with the I/O ports.)
Figure 5
shows the I/O port configurations. The DATAand CONFIGU-
RATION registers allow for each port bit to be individually
configured under software control as shown below:
PORT L is a 4-bit I/O port.All L-pins have Schmitt triggers on
the inputs.
The Port L supports Multi-Input Wake Up on all four pins.
The Port L has the following alternate features:
L7 MIWU or external interrupt
L6 MIWU or external interrupt
L5 MIWU or external interrupt
L4 MIWU or external interrupt
Configuration Data Port Set-Up
Register Register
0 0 Hi-Z Input (TRI-STATE Output)
0 1 Input with Weak Pull-Up
1 0 Push-Pull Zero Output
1 1 Push-Pull One Output
Please note:
The lower 4 L-bits read all ones (L0:L3). This is independant
from the states of the associated bits in the L-port Data- and
Configuration register. The lower 4 bits in the L-port Data-
and Configuration register can be used as general purpose
status indicators (flags).
Port G is an 8-bit port with 5 I/O pins (G0, G2–G5), an input
pin (G6), and a dedicated output pin (G7). Pins G0 and
G2–G6 all have Schmitt Triggers on their inputs. Pin G1
serves as the dedicated WDOUT WATCHDOG output, while
pin G7 is either input or output depending on the oscillator
mask option selected. With the crystal oscillator option se-
lected, G7 serves as the dedicated output pin for the CKO
clock output. With the single-pin R/C oscillator mask option
selected, G7 serves as a general purpose input pin but is
also used to bring the devices out of HALT mode with a low
to high transition on G7. There are two registers associated
with the G Port, a data register and a configuration register.
Therefore, each of the 5 I/O bits (G0, G2–G5) can be indi-
vidually configured under software control.
Since G6 is an input only pin and G7 is the dedicated CKO
clock output pin (crystal clock option) or general purpose in-
put (R/C clock option), the associated bits in the data and
configuration registers for G6 and G7 are used for special
purpose functions as outlined below. Reading the G6 and G7
data bits will return zeros.
Note that the chip will be placed in the HALT mode by writing
a “1” to bit 7 of the Port G Data Register. Similarly the chip
will be placed in the IDLE mode by writing a “1” to bit 6 of the
Port G Data Register.
Writing a “1” to bit 6 of the Port G Configuration Register en-
ables the MICROWIRE/PLUS to operate with the alternate
phase of the SK clock. The G7 configuration bit, if set high,
enables the clock start up delay after HALT when the R/C
clock configuration is used.
Config Reg. Data Reg.
G7 CLKDLY HALT
G6 Alternate SK IDLE
Port G has the following alternate features:
G6 SI (MICROWIRE Serial Data Input)
G5 SK (MICROWIRE Serial Clock)
G4 SO (MICROWIRE Serial Data Output)
G3 T1A (Timer T1 I/O)
G2 T1B (Timer T1 Capture Input)
G0 INTR (External Interrupt Input)
Port G has the following dedicated functions:
G7 CKO Oscillator dedicated output or general purpose
input
G1 WDOUT WATCHDOG and/or Clock Monitor dedicated
output.
Port I is an eight-bit Hi-Z input port.
Port I0–I7 are used for the analog function block.
The Port I has the following alternate features:
I7 C
OUT
(Comparator Output)
I6 Analog CH6 (Comparator Positive Input 6)
I5 Analog CH5 (Comparator Positive Input 5)
I4 Analog CH4 (Comparator Positive Input 4)
I3 Analog CH3 (Comparator Positive Input 3/Comparator
Output)
I2 Analog CH2 (Comparator Positive Input 2)
I1 I
SRC
(Comparator Negative Input/Current Source Out)
I0 Analog CH1 (Comparator Positive Input 1)
Port D is a 4-bit output port that is preset high when RESET
goes low. The user can tie two or more D port outputs (ex-
cept D2) together in order to get a higher drive.
DS012865-52
FIGURE 5. I/P Port Configurations
COP8ACC Family
www.national.com11
Functional Description
The architecture of the devices is a modified Harvard archi-
tecture. With the Harvard architecture, the control store pro-
gram memory (ROM) is separated from the data store
memory (RAM). Both ROM and RAM have their own sepa-
rate addressing space with separate address buses. The ar-
chitecture, though based on the Harvard architecture, per-
mits transfer of data from ROM to RAM.
CPU REGISTERS
The CPU can do an 8-bit addition, subtraction, logical or shift
operation in one instruction (t
C
) cycle time.
There are six CPU registers:
A is the 8-bit Accumulator Register
PC®is the 15-bit Program Counter Register
PU is the upper 7 bits of the program counter (PC)
PL is the lower 8 bits of the program counter (PC)
B is an 8-bit RAM address pointer, which can be optionally
post auto incremented or decremented.
X is an 8-bit alternate RAM address pointer, which can be
optionally post auto incremented or decremented.
SP is the 8-bit stack pointer, which points to the subroutine/
interrupt stack (in RAM). The SP is initialized to RAM ad-
dress 06F with reset.
All the CPU registers are memory mapped with the excep-
tion of the Accumulator (A) and the Program Counter (PC).
PROGRAM MEMORY
The program memory consists of 4096 bytes of ROM a OTP
EPROM. These bytes may hold program instructions or con-
stant data (data tables for the LAID instruction, jump vectors
for the JID instruction, and interrupt vectors for the VIS in-
struction). The program memory is addressed by the 15-bit
program counter (PC). All interrupts in the devices vector to
program memory location 0FF Hex.
The COP8ACC7 device can be configured to inhibit external
reads of the program memory. This is done by programming
the Security Byte.
SECURITY FEATURE
The program memory array has an associate Security Byte
that is located outside of the program address range. This
byte can be addressed only from programming mode by a
programmer tool.
Security is an optional feature and can only be asserted after
the memory array has been programmed and verified. A se-
cured part will read all 00(hex) by a programmer. The part
will fail Blank Check and will fail Verify operations. A Read
operation will fill the programmer’s memory with 00(hex).
The Security Byte itself is always readable with value of
00(hex) if unsecure and FF(hex) if secure.
DATA MEMORY
The data memory address space includes the on-chip RAM
and data registers, the I/O registers (Configuration, Data and
Pin), the control registers, the MICROWIRE/PLUS SIO shift
register, and the various registers, and counters associated
with the timers (with the exception of the IDLE timer). Data
memory is addressed directly by the instruction or indirectly
by the B, X, and SP pointers.
The data memory consists of 128 bytes of RAM. Sixteen
bytes of RAM are mapped as “registers” at addresses 0F0 to
0FF Hex. These registers can be loaded immediately, and
also decremented and tested with the DRSZ (decrement
register and skip if zero) instruction. The memory pointer
registers X, B and SP are memory mapped into this space at
address locations 0FC to 0FF Hex respectively, with the
other registers being available for general usage.
The instruction set permits any bit in memory to be set, reset
or tested. All I/O and registers (except A and PC) are
memory mapped; therefore, I/O bits and register bits can be
directly and individually set, reset and tested. The accumula-
tor (A) bits can also be directly and individually tested.
Note: RAM contents are undefined upon power-up.
Reset
The RESET input when pulled low initializes the microcon-
troller. Initialization will occur whenever the RESET input is
pulled low. Upon initialization, the data and configuration
registers for ports L and G are cleared, resulting in these
Ports being initialized to the TRI-STATE mode. Pin G1 of the
G Port is an exception (as noted below) since pin G1 is dedi-
cated as the WATCHDOG and/or Clock Monitor error output
pin. Port D is set high. The PC, PSW, ICNTRL and
CNTRL-control registers are cleared. The Comparator Se-
lect Register is cleared. The S register is initialized to zero.
The Multi-Input Wakeup registers WKEN and WKEDG are
cleared. Wakeup register WKPND is unknown. The stack
pointer, SP, is initialized to 6F Hex.
The devices come out of reset with both the WATCHDOG
logic and the Clock Monitor detector armed, with the
WATCHDOG service window bits set and the Clock Monitor
bit set. The WATCHDOG and Clock Monitor circuits are in-
hibited during reset. The WATCHDOG service window bits
being initialized high default to the maximum WATCHDOG
service window of 64k t
C
clock cycles. The Clock Monitor bit
being initialized high will cause a Clock Monitor error follow-
ing reset if the clock has not reached the minimum specified
frequency at the termination of reset. A Clock Monitor error
will cause an active low error output on pin G1. This error
output will continue until 16 t
C
-32 t
C
clock cycles following
the clock frequency reaching the minimum specified value,
at which time the G1 output will enter the TRI-STATE mode.
The external RC network shown in
Figure 6
should be used
to ensure that the RESET pin is held low until the power sup-
ply to the chip stabilizes.
WARNING:
When the devices are held in reset for a long time they will
consume high current (typically about 7 mA). This is not true
for the equivalent ROM device (COP8ACC5).
Oscillator Circuits
The chip can be driven by a clock input on the CKI input pin
which can be between DC and 10 MHz. The CKO output
clock is on pin G7 (crystal configuration). The CKI input fre-
quency is divided down by 10 to produce the instruction
cycle clock (t
C
).
COP8ACC Family
www.national.com 12
Oscillator Circuits (Continued)
Figure 7
shows the Crystal and R/C Oscillator diagrams.
CRYSTAL OSCILLATOR
CKI and CKO can be connected to make a closed loop crys-
tal (or resonator) controlled oscillator.
Table 1
shows the component values required for various
standard crystal values.
TABLE 1. Crystal Oscillator Configuration, T
A
= 25˚C
R1 R2 C1 C2 CKI Freq Conditions
(kΩ)(MΩ) (pF) (pF) (MHz)
0 1 30 30–36 10 V
CC
=5V
0 1 30 30–36 4 V
CC
=5V
0 1 200 100–150 0.455 V
CC
=5V
R/C OSCILLATOR
By selecting CKI as a single pin oscillator input, a single pin
R/C oscillator circuit can be connected to it. CKO is available
as a general purpose input, and/or HALT restart input.
Note: Use of the R/C oscillator option will result in higher electromagnetic
emissions.
Table 2
shows the variation in the oscillator frequencies as
functions of the component (R and C) values.
TABLE 2. RC Oscillator Configuration, T
A
= 25˚C
R C CKI Freq Instr. Cycle Conditions
(kΩ) (pF) (MHz) (µs)
3.3 82 2.2 to 2.7 3.7 to 4.6 V
CC
=5V
5.6 100 1.1 to 1.3 7.4 to 9.0 V
CC
=5V
6.8 100 0.9 to 1.1 8.8 to 10.8 V
CC
=5V
Note 18: 3k ≤R≤200k
Note 19: 50 pF ≤C≤200 pF
Control Registers
CNTRL Register (Address X'00EE)
T1C3 T1C2 T1C1 T1C0 MSEL IEDG SL1 SL0
Bit 7 Bit 0
The Timer1 (T1) and MICROWIRE/PLUS control register
contains the following bits:
T1C3 Timer T1 mode control bit
T1C2 Timer T1 mode control bit
T1C1 Timer T1 mode control bit
T1C0 Timer T1 Start/Stop control in timer
modes 1 and 2, T1 Underflow Interrupt
Pending Flag in timer mode 3
MSEL Selects G5 and G4 as MICROWIRE/PLUS
signals SK and SO respectively
IEDG External interrupt edge polarity select
(0 = Rising edge, 1 = Falling edge)
SL1 & SL0 Select the MICROWIRE/PLUS clock divide
by (00 = 2, 01 = 4, 1x = 8)
PSW Register (Address X'00EF)
HC C T1PNDA T1ENA EXPND BUSY EXEN GIE
Bit 7 Bit 0
The PSW register contains the following select bits:
HC Half Carry Flag
C Carry Flag
T1PNDA Timer T1 Interrupt Pending Flag (Autoreload
RA in mode 1, T1 Underflow in Mode 2, T1A
capture edge in mode 3)
T1ENA Timer T1 Interrupt Enable for Timer Underflow
or T1A Input capture edge
EXPND External interrupt pending
BUSY MICROWIRE/PLUS busy shifting flag
EXEN Enable external interrupt
GIE Global interrupt enable (enables interrupts)
The Half-Carry flag is also affected by all the instructions that
affect the Carry flag. The SC (Set Carry) and R/C (Reset
Carry) instructions will respectively set or clear both the carry
flags. In addition to the SC and R/C instructions, ADC,
SUBC, RRC and RLC instructions affect the Carry and Half
Carry flags.
ICNTRL Register (Address X'00E8)
Reserved LPEN T0PND T0EN µWPND µWEN T1PNDB T1ENB
Bit 7 Bit 0
The ICNTRL register contains the following bits:
Reserved This bit is reserved and should be zero.
DS012865-53
RC >5 x POWER SUPPLY RISE TIME
FIGURE 6. Recommended Reset Circuit
DS012865-54
DS012865-55
FIGURE 7. Crystal and R/C Oscillator Diagrams
COP8ACC Family
www.national.com13
Control Registers (Continued)
LPEN L Port Interrupt Enable (Multi-Input Wakeup/
Interrupt)
T0PND Timer T0 Interrupt pending
T0EN Timer T0 Interrupt Enable (Bit 12 toggle)
µWPND MICROWIRE/PLUS interrupt pending
µWEN Enable MICROWIRE/PLUS interrupt
T1PNDB Timer T1 Interrupt Pending Flag for T1B cap-
ture edge
T1ENB Timer T1 Interrupt Enable for T1B Input cap-
ture edge
Timers
The devices contain a very versatile set of timers (T0 and
T1). All timers and associated autoreload/capture registers
power up containing random data.
TIMER T0 (IDLE TIMER)
The devices support applications that require maintaining
real time and low power with the IDLE mode. This IDLE
mode support is furnished by the IDLE timer T0, which is a
16-bit timer. The Timer T0 runs continuously at the fixed rate
of the instruction cycle clock, t
C
. The user cannot read or
write to the IDLE Timer T0, which is a count down timer.
The Timer T0 supports the following functions:
•Exit out of the Idle Mode (See Idle Mode description)
•WATCHDOG logic (See WATCHDOG description)
•Start up delay out of the HALT mode
Figure 8
is a functional block diagram showing the structure
of the IDLE Timer and its associated interrupt logic.
Bits 11 through 15 of the ITMR register can be selected for
triggering the IDLE Timer interrupt. Each time the selected
bit underflows (every 4k, 8k, 16k, 32k or 64k instruction
cycles), the IDLE Timer interrupt pending bit T0PND is set,
thus generating an interrupt (if enabled), and bit 6 of the Port
G data register is reset, thus causing an exit from the IDLE
mode if the devices are in that mode.
In order for an interrupt to be generated, the IDLE Timer in-
terrupt enable bit T0EN must be set, and the GIE (Global In-
terrupt Enable) bit must also be set. The T0PND flag and
T0EN bit are bits 5 and 4 of the ICNTRL register, respec-
tively. The interrupt can be used for any purpose. Typically, it
is used to perform a task upon exit from the IDLE mode. For
more information on the IDLE mode, refer to the Power Save
Modes section.
The Idle Timer period is selected by bits 0–2 of the ITMR
register Bits 3–7 of the ITMR Register are reserved and
should not be used as software flags.
ITMR Register (Address X’0xCF)
Reserved ITSEL2 ITSEL1 ITSEL0
Bit 7 Bit 3 Bit 0
TABLE 3. Idle Timer Window Length
ITSEL2 ITSEL1 ITSEL0 Idle Timer Period
(Instruction Cycles)
0 0 0 4,096
0 0 1 8,192
0 1 0 16,384
0 1 1 32,768
1 X X 65,536
The ITMR register is cleared on Reset and the Idle Timer pe-
riod is reset to 4,096 instruction cycles.
Any time the IDLE Timer period is changed there is the pos-
sibility of generating a spurious IDLE Timer interrupt by set-
ting the T0PND bit. The user is advised to disable IDLE
Timer interrupts prior to changing the value of the ITSEL bits
of the ITMR Register and then clear the T0PND bit before at-
tempting to synchronize operation to the IDLE Timer.
DS012865-56
FIGURE 8. Functional Block Diagram for Idle Timer T0
COP8ACC Family
www.national.com 14
Timers (Continued)
TIMER T1
The devicea have a powerful timer/counter block. The timer
consists of a 16-bit timer, T1, and two supporting 16-bit
autoreload/capture registers, R1A and R1B. The timer block
has two pins associated with it, T1A and T1B. The pin T1A
supports I/O required by the timer block, while the pin T1B is
an input to the timer block. The powerful and flexible timer
block allows the devices to easily perform all timer functions
with minimal software overhead. The timer block has three
operating modes: Processor Independent PWM mode, Ex-
ternal Event Counter mode, and Input Capture mode.
The control bits T1C3,T1C2, and T1C1 allow selection of the
different modes of operation.
Mode 1. Processor Independent PWM Mode
As the name suggests, this mode allows the devices to gen-
erate a PWM signal with very minimal user intervention. The
user only has to define the parameters of the PWM signal
(ON time and OFF time). Once begun, the timer block will
continuously generate the PWM signal completely indepen-
dent of the microcontroller. The user software services the
timer block only when the PWM parameters require updat-
ing.
In this mode the timer T1 counts down at a fixed rate of t
C
.
Upon every underflow the timer is alternately reloaded with
the contents of supporting registers, R1A and R1B. The very
first underflow of the timer causes the timer to reload from
the register R1A. Subsequent underflows cause the timer to
be reloaded from the registers alternately beginning with the
register R1B.
The T1 Timer control bits, T1C3, T1C2 and T1C1 set up the
timer for PWM mode operation.
Figure 9
shows a block diagram of the timer in PWM mode.
The underflows can be programmed to toggle the T1Aoutput
pin. The underflows can also be programmed to generate in-
terrupts.
Underflows from the timer are alternately latched into two
pending flags, T1PNDA and T1PNDB. The user must reset
these pending flags under software control. Two control en-
able flags, T1ENA and T1ENB, allow the interrupts from the
timer underflow to be enabled or disabled. Setting the timer
enable flag T1ENA will cause an interrupt when a timer un-
derflow causes the R1A register to be reloaded into the
timer. Setting the timer enable flag T1ENB will cause an in-
terrupt when a timer underflow causes the R1B register to be
reloaded into the timer. Resetting the timer enable flags will
disable the associated interrupts.
Either or both of the timer underflow interrupts may be en-
abled. This gives the user the flexibility of interrupting once
per PWM period on either the rising or falling edge of the
PWM output. Alternatively, the user may choose to interrupt
on both edges of the PWM output.
Mode 2. External Event Counter Mode
This mode is quite similar to the processor independent
PWM mode previously described. The main difference is that
the timer, T1, is clocked by the input signal from the T1Apin.
The T1 timer control bits, T1C3, T1C2 and T1C1 allow the
timer to be clocked either on a positive or negative edge from
the T1A pin. Underflows from the timer are latched into the
T1PNDA pending flag. Setting the T1ENA control flag will
cause an interrupt when the timer underflows.
In this mode the input pin T1B can be used as an indepen-
dent positive edge sensitive interrupt input if the T1ENB con-
trol flag is set. The occurrence of a positive edge on the T1B
input pin is latched into the T1PNDB flag.
Figure 10
shows a block diagram of the timer in External
Event Counter mode.
Note: The PWM output is not available in this mode since the T1A pin is be-
ing used as the counter input clock.
DS012865-57
FIGURE 9. Timer in PWM Mode
DS012865-58
FIGURE 10. Timer in External Event Counter Mode
COP8ACC Family
www.national.com15
Timers (Continued)
Mode 3. Input Capture Mode
The devices can precisely measure external frequencies or
time external events by placing the timer block, T1, in the in-
put capture mode.
In this mode, the timer T1 is constantly running at the fixed t
C
rate. The two registers, R1A and R1B, act as capture regis-
ters. Each register acts in conjunction with a pin. The register
R1A acts in conjunction with the T1A pin and the register
R1B acts in conjunction with the T1B pin.
The timer value gets copied over into the register when a
trigger event occurs on its corresponding pin. Control bits,
T1C3, T1C2 and T1C1, allow the trigger events to be speci-
fied either as a positive or a negative edge. The trigger con-
dition for each input pin can be specified independently.
The trigger conditions can also be programmed to generate
interrupts. The occurrence of the specified trigger condition
on the T1Aand T1B pins will be respectively latched into the
pending flags, T1PNDA and T1PNDB. The control flag
T1ENA allows the interrupt on T1A to be either enabled or
disabled. Setting the T1ENA flag enables interrupts to be
generated when the selected trigger condition occurs on the
T1A pin. Similarly, the flag T1ENB controls the interrupts
from the T1B pin.
Underflows from the timer can also be programmed to gen-
erate interrupts. Underflows are latched into the timer T1C0
pending flag (the T1C0 control bit serves as the timer under-
flow interrupt pending flag in the Input Capture mode). Con-
sequently, the T1C0 control bit should be reset when enter-
ing the Input Capture mode. The timer underflow interrupt is
enabled with the T1ENA control flag. When a T1A interrupt
occurs in the Input Capture mode, the user must check both
the T1PNDA and T1C0 pending flags in order to determine
whether a T1A input capture or a timer underflow (or both)
caused the interrupt.
Figure 11
shows a block diagram of the timer in Input Cap-
ture mode.
TIMER CONTROL FLAGS
The control bits and their functions are summarized below.
T1C3 Timer mode control
T1C2 Timer mode control
T1C1 Timer mode control
T1C0 Timer Start/Stop control in Modes 1 and 2 (Pro-
cessor Independent PWM and External Event
Counter), where 1 = Start, 0 = Stop
Timer Underflow Interrupt Pending Flag in
Mode 3 (Input Capture)
T1PNDA Timer Interrupt Pending Flag
T1ENA Timer Interrupt Enable Flag
1 = Timer Interrupt Enabled
0 = Timer Interrupt Disabled
T1PNDB Timer Interrupt Pending Flag
T1ENB Timer Interrupt Enable Flag
1 = Timer Interrupt Enabled
0 = Timer Interrupt Disabled
The timer mode control bits (T1C3, T1C2 and T1C1) are detailed below:
Mode T1C3 T1C2 T1C1 Description Interrupt A
Source Interrupt B
Source Timer
Counts On
11 0 1 PWM: T1A Toggle Autoreload RA Autoreload RB t
C
1 0 0 PWM: No T1A
Toggle Autoreload RA Autoreload RB t
C
2
0 0 0 External Event
Counter Timer
Underflow Pos. T1B Edge Pos. T1A
Edge
0 0 1 External Event
Counter Timer
Underflow Pos. T1B Edge Pos. T1A
Edge
DS012865-59
FIGURE 11. Timer in Input Capture Mode
COP8ACC Family
www.national.com 16
Timers (Continued)
Mode T1C3 T1C2 T1C1 Description Interrupt A
Source Interrupt B
Source Timer
Counts On
3
0 1 0 Captures: Pos. T1A Edge Pos. T1B Edge t
C
T1A Pos. Edge or Timer
T1B Pos. Edge Underflow
1 1 0 Captures: Pos. T1A Neg. T1B t
C
T1A Pos. Edge Edge or Timer Edge
T1B Neg. Edge Underflow
0 1 1 Captures: Neg. T1A Neg. T1B t
C
T1A Neg. Edge Edge or Timer Edge
T1B Neg. Edge Underflow
1 1 1 Captures: Neg. T1A Neg. T1B t
C
T1A Neg. Edge Edge or Timer Edge
T1B Neg. Edge Underflow
HIGH SPEED CAPTURE TIMER
The devices provide a 16-bit high-speed capture timer. The
timer consists of a 16-bit up-counter that is clocked with the
device clock input frequency (CKI) and an 8-bit control regis-
ter. The 16-bit counter is mapped as two read/write 8-bit reg-
isters. This timer is specifically designed to be used in con-
junction with the Analog Function Block (comparator, analog
multiplexer, constant current source) to implement a
low-cost, high-resolution, single-slope A/D.
The timer is automatically stopped in the event of a capture
to allow the software to read the timer value. Coming out of
reset the counter is disabled (stopped) and reads all “0”.
Setting the Capture Timer Run bit CAPRUN bit in the Cap-
ture Control Register (CAPCNTL) will start the counter. The
counter will count up until a capture event (negative edge) is
received. Upon a capture the counter will be stopped, the
Capture Pending bit (CAPPND) is set, and the CAPRUN bit
is automatically reset. If capture interrupts are enabled
(CAPIEN=1), the capture event will generate an interrupt.
Setting the CAPRUN bit again by software will start a new
counting cycle. If the Capture Mode bit is reset (CAP-
MOD=0) the capture timer will be automatically initialized to
all “0” with each setting of the CAPRUN bit. If CAPMOD=1
the timer will not be cleared when setting the CAPRUN bit,
thus allowing the user’s software to pre-load the timer regis-
ters with any desired value. This mode can be used in con-
junction with the timer’s overflow to implement for example a
programmable delay counter.
“CAPTURE MODE” is only active when the CAPRUN bit is
set, i.e. any capture events received while the timer is
stopped (CAPRUN=0) will be ignored and will not cause the
CAPPND bit to be set. The capture counter can also be
stopped (frozen) by the user’s software resetting the CA-
PRUN bit.
If the user program tries to set the CAPRUN bit at the same
time that the hardware gets a capture event and tries to reset
the CAPRUN bit, the hardware will have precedence.
Should the counter overflow before a capture condition oc-
curs, the Capture Overflow bit (CAPOVL) bit in the
CAPCNTL register will be set. If Capture interrupts are en-
abled (CAPIEN=1) an overflow will generate an interrupt.
The user software should reset this bit before the next over-
flow occurs, otherwise subsequent overflow conditions can-
not be detected.
Capture Overflow interrupt and Capture Pending interrupt
share the same interrupt vector.
CAPCNTL Register (Address (X’CE)
Reserved CAPMOD CAPRUN CAPOVL CAPPND CAPIEN
Bit 7-5 Bit 4 Bit 0
The CAPCNTL register contains the following bits:
Reserved These bits are reserved and should must be
zero.
CAPMOD Reset Time.
0: reset timer to “0” when CAPRUN bit gets set
1: DO NOT reset timer to “0” when CAPRUN bit
gets set.
CAPRUN Capture Timer Run. Setting this bit to one will
start the capture timer. This bit gets automatically
reset to “0” when a capture events occurs. Writ-
ing a “0” by software will also reset the bit and
stop the timer.
CAPOVL Capture Timer Overflow. Gets set to “1” upon
timer overflow. Has to be reset by user’s soft-
ware. If CAPIEN = 1 an interrupt is generated.
CAPPND Capture pending.
Gets automatically set when a capture event oc-
curs. If CAPIEN = 1 an interrupt is generated.
Has to be reset by the user’s software.
CAPIEN Capture Interrupt enable,
1 = enable interrupts, 0 = disable interrupts
Power Save Modes
The devices offer the user two power save modes of opera-
tion: HALT and IDLE. In the HALT mode, all microcontroller
activities are stopped. In the IDLE mode, the on-board oscil-
lator circuitry and timer T0 are active but all other microcon-
troller activities are stopped. In either mode, all on-board
RAM, registers, I/O states, and timers (with the exception of
T0) are unaltered.
HALT MODE
The devices can be placed in the HALTmode by writing a “1”
to the HALT flag (G7 data bit). All microcontroller activities,
including the clock and timers, are stopped. The WATCH-
COP8ACC Family
www.national.com17
Power Save Modes (Continued)
DOG logic on the devices is disabled during the HALT mode.
However, the clock monitor circuitry, if enabled, remains ac-
tive and will cause the WATCHDOG output pin (WDOUT) to
go low. If the HALT mode is used and the user does not want
to activate the WDOUT pin, the Clock Monitor should be dis-
abled after the devices come out of reset (resetting the Clock
Monitor control bit with the first write to the WDSVR register).
In the HALT mode, the power requirements of the devices
are minimal and the applied voltage (V
CC
) may be de-
creased to V
r
(V
r
= 2.0V) without altering the state of the ma-
chine.
The devices support three different ways of exiting the HALT
mode. The first method of exiting the HALT mode is with the
Multi-Input Wakeup feature on the Port L.
The second method is with a low to high transition on the
CKO (G7) pin. This method precludes the use of the crystal
clock configuration (since CKO becomes a dedicated out-
put), and so may only be used with an RC clock configura-
tion. The third method of exiting the HALT mode is by pulling
the RESET pin low.
Since a crystal or ceramic resonator may be selected as the
oscillator, the Wakeup signal is not allowed to start the chip
running immediately since crystal oscillators and ceramic
resonators have a delayed start up time to reach full ampli-
tude and frequency stability. The IDLE timer is used to gen-
erate a fixed delay to ensure that the oscillator has indeed
stabilized before allowing instruction execution. In this case,
upon detecting a valid Wakeup signal, only the oscillator cir-
cuitry is enabled. The IDLE timer is loaded with a value of
256 and is clocked with the t
C
instruction cycle clock. The t
C
clock is derived by dividing the oscillator clock down by a fac-
tor of 10. The Schmitt trigger following the CKI inverter on
the chip ensures that the IDLE timer is clocked only when the
oscillator has a sufficiently large amplitude to meet the
Schmitt trigger specifications. This Schmitt trigger is not part
of the oscillator closed loop. The startup timeout from the
IDLE timer enables the clock signals to be routed to the rest
of the chip.
If an RC clock option is being used, the fixed delay is intro-
duced optionally. A control bit, CLKDLY, mapped as configu-
ration bit G7, controls whether the delay is to be introduced
or not. The delay is included if CLKDLY is set, and excluded
if CLKDLY is reset. The CLKDLY bit is cleared on reset.
The devices have two mask options associated with the
HALT mode. The first mask option enables the HALT mode
feature, while the second mask option disables the HALT
mode. With the HALT mode enable mask option, the devices
will enter and exit the HALT mode as described above. With
the HALT disable mask option, the devices cannot be placed
in the HALT mode (writing a “1” to the HALT flag will have no
effect, the HALT flag will remain “0”).
IDLE MODE
In the IDLE mode, program execution stops and power con-
sumption is reduced to a very low level as with the HALT
mode. However, the on-board oscillator, IDLE Timer (Timer
T0), and Clock Monitor continue to operate, allowing real
time to be maintained. The devices remain idle for a selected
amount of time up to 65,536 instruction cycles, or 65.536 mil-
liseconds with a 1 MHz instruction clock frequency, and then
automatically exits the IDLE mode and returns to normal pro-
gram execution.
The devices are placed in the IDLE mode under software
control by setting the IDLE bit (bit 6 of the Port G data regis-
ter).
The IDLE timer window is selectable from one of five values,
4k, 8k, 16k, 32k or 64k instruction cycles. Selection of this
value is made through the ITMR register.
The IDLE mode uses the on-chip IDLE Timer (Timer T0) to
keep track of elapsed time in the IDLE state. The IDLE timer
runs continuously at the instruction clock rate, whether or not
the devices are in the IDLE mode. Each time the bit of the
timer associated with the selected window toggles, the
T0PND bit is set, an interrupt is generated (if enabled), and
the devices exit the IDLE mode if in that mode. If the IDLE
timer interrupt is enabled, the interrupt is serviced before ex-
ecution of the main program resumes. (However, the instruc-
tion which was started as the part entered the IDLE mode is
completed before the interrupt is serviced. This instruction
should be a NOP which should follow the enter IDLE instruc-
tion.) The user must reset the IDLE timer pending flag
(T0PND) before entering the IDLE mode.
As with the HALT mode, these devices can also be returned
to normal operation with a reset, or with a Multi-Input
Wakeup input. Upon reset the ITMR register is cleared and
the ITMR register selects the 4,096 instruction cycle tap of
the Idle Timer.
The IDLE timer cannot be started or stopped under software
control, and it is not memory mapped, so it cannot be read or
written by the software. Its state upon Reset is unknown.
Therefore, if the devices are put into the IDLE mode at an ar-
bitrary time, it will stay in the IDLE mode for somewhere be-
tween 1 and the selected number of instruction cycles.
In order to precisely time the duration of the IDLE state, entry
into the IDLE mode must be synchronized to the state of the
IDLE Timer. The best way to do this is to use the IDLE Timer
interrupt, which occurs on every underflow of the bit of the
IDLE Timer which is associated with the selected window.
Another method is to poll the state of the IDLE Timer pending
bit T0PND, which is set on the same occurrence. The Idle
Timer interrupt is enabled by setting bit T0EN in the ICNTRL
register.
Any time the IDLE Timer window length is changed there is
the possibility of generating a spurious IDLE Timer interrupt
by setting the T0PND bit. The user is advised to disable
IDLE Timer interrupts prior to changing the value of the IT-
SEL bits of the ITMR Register and then clear the TOPND bit
before attempting to synchronize operation to the IDLE
Timer.
Note: As with the HALT mode, it is necessary to program two NOP’s to allow
clock resynchronization upon return from the IDLE mode. The NOP’s
are placed either at the beginning of the IDLE timer interrupt routine or
immediately following the “enter IDLE mode” instruction.
For more information on the IDLE Timer and its associated
interrupt, see the description in the Timers section.
Multi-Input Wakeup
The Multi-Input Wakeup feature is used to return (wakeup)
the devices from either the HALT or IDLE modes.Alternately
Multi-Input Wakeup/Interrupt feature may also be used to
generate up to 4 edge selectable external interrupts.
Figure 12
shows the Multi-Input Wakeup logic.
The Multi-Input Wakeup feature utilizes the L Port. The user
selects which particular L port bit (or combination of L Port
bits) will cause the devices to exit the HALT or IDLE modes.
The selection is done through the register WKEN. The regis-
COP8ACC Family
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Multi-Input Wakeup (Continued)
ter WKEN is an 8-bit read/write register, which contains a
control bit for every L port bit. Setting a particular WKEN bit
enables a Wakeup from the associated L port pin.
The user can select whether the trigger condition on the se-
lected L Port pin is going to be either a positive edge (low to
high transition) or a negative edge (high to low transition).
This selection is made via the register WKEDG, which is an
8-bit control register with a bit assigned to each L Port pin.
Setting the control bit will select the trigger condition to be a
negative edge on that particular L Port pin. Resetting the bit
selects the trigger condition to be a positive edge. Changing
an edge select entails several steps in order to avoid a
Wakeup condition as a result of the edge change. First, the
associated WKEN bit should be reset, followed by the edge
select change in WKEDG. Next, the associated WKPND bit
should be cleared, followed by the associated WKEN bit be-
ing re-enabled.
An example may serve to clarify this procedure. Suppose we
wish to change the edge select from positive (low going high)
to negative (high going low) for L Port bit 5, where bit 5 has
previously been enabled for an input interrupt. The program
would be as follows:
RBIT 5, WKEN ; Disable MIWU
SBIT 5, WKEDG ; Change edge polarity
RBIT 5, WKPND ; Reset pending flag
SBIT 5, WKEN ; Enable MIWU
If the L port bits have been used as outputs and then
changed to inputs with Multi-Input Wakeup/Interrupt, a safety
procedure should also be followed to avoid wakeup condi-
tions. After the selected L port bits have been changed from
output to input but before the associated WKEN bits are en-
abled, the associated edge select bits in WKEDG should be
set or reset for the desired edge selects, followed by the as-
sociated WKPND bits being cleared.
This same procedure should be used following reset, since
the L port inputs are left floating as a result of reset.
The occurrence of the selected trigger condition for
Multi-Input Wakeup is latched into a pending register called
WKPND. The respective bits of the WKPND register will be
set on the occurrence of the selected trigger edge on the cor-
responding Port L pin. The user has the responsibility of
clearing these pending flags. Since WKPND is a pending
register for the occurrence of selected wakeup conditions,
the devices will not enter the HALT mode if any Wakeup bit
is both enabled and pending. Consequently, the user must
clear the pending flags before attempting to enter the HALT
mode.
WKEN, WKPND and WKEDG are all read/write registers,
and are cleared at reset.
PORT L INTERRUPTS
Port L provides the user with an additional eight fully select-
able, edge sensitive interrupts which are all vectored into the
same service subroutine.
The interrupt from Port L shares logic with the wake up cir-
cuitry. The register WKEN allows interrupts from Port L to be
individually enabled or disabled. The register WKEDG speci-
fies the trigger condition to be either a positive or a negative
edge. Finally, the register WKPND latches in the pending
trigger conditions.
The GIE (Global Interrupt Enable) bit enables the interrupt
function.
DS012865-60
FIGURE 12. Multi-Input Wake Up Logic
COP8ACC Family
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Multi-Input Wakeup (Continued)
A control flag, LPEN, functions as a global interrupt enable
for Port L interrupts. Setting the LPEN flag will enable inter-
rupts and vice versa. A separate global pending flag is not
needed since the register WKPND is adequate.
Since Port L is also used for waking the devices out of the
HALT or IDLE modes, the user can elect to exit the HALT or
IDLE modes either with or without the interrupt enabled. If he
elects to disable the interrupt, then the devices will restart
execution from the instruction immediately following the in-
struction that placed the microcontroller in the HALT or IDLE
modes. In the other case, the devices will first execute the in-
terrupt service routine and then revert to normal operation.
(See HALT MODE for clock option wakeup information.)
Analog Function Block
This device contains an analog function block with the intent
to provide a function which allows for single slope, low cost,
A/D conversion of up to 6 channels.
CMPSL REGISTER (ADDRESS X’00B7)
CMPT2B CMPISEL2 CMPISEL1 CMPISEL0 CMPOE CSEN CMPEN CMPNEG
Bit 7 Bit 0
The CMPSL register contains the following bits:
CMPT2B Selects the “High Speed 16-bit Capture
Timer” input to be driven directly by the
comparator output. If the comparator is dis-
abled (CMPEN=0), this function is dis-
abled, i.e. the Capture Timer input is con-
nected to GND.
CMPISEL0/1/2 Will select one of seven possible sources
(I0/I2/I3/I4/I5/I6/internal reference) as a
positive input to the comparator (see
Table
4
for more information)
CMPOE Enables the comparator output to either pin
I3 or pin I7 (“1”=enable) depending on the
value of CMPISEL0/1/2.
CSEN Enables the internal constant current
source. This current source provides a
nominal 20 µA constant current at the I1
pin. This current can be used to ensure a
linear charging rate on an external capaci-
tor. This bit has no affect and the current
source is disabled if the comparator is not
enabled (CMPEN=0).
CMPEN Enable the comparator (“1” = enable)
CMPNEG Will drive I1 to a low level. This bit can be
used to discharge an external capacitor.
This bit is disabled if the comparator is not
enabled (CMPEN=0).
The Comparator Select Register is cleared on RESET (the
comparator is disabled). To save power the program should
also disable the comparator before the µC enters the HALT/
IDLE modes. Disabling the comparator will turn off the con-
stant current source and the V
CC
/2 reference, disconnect the
comparator output from the Capture Timer input and pin I3/I7
and remove the low on I1 caused by CMPNEG.
It is often useful for the user’s program to read the result of
a comparator operation. Since I1 is always selected to be
COMPIN—when the comparator is enabled (CMPEN=1),
the comparator output can be read internally by reading bit 1
(CMPRD) of register PORTI (RAM address 0xD7).
The following table lists the comparator inputs and outputs
versus the value of the CMPISEL0/1/2 bits. The output will
only be driven if the CMPOE bit is set to 1.
DS012865-61
FIGURE 13. Analog Function Block
COP8ACC Family
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Analog Function Block (Continued)
TABLE 4. Comparator Input Selection
Control Bit Comparator
Comparator
Output
Input Source
CMPISEL2 CMPISEL1 CMPISEL0 Neg. Pos.
Input Input
0 0 0 I1 I2 CH2 I3
0 0 1 I1 I2 CH2 I7
0 1 0 I1 I3 CH3 I7
0 1 1 I1 I0 CH1 I7
1 0 0 I1 I4 CH4 I7
1 0 1 I1 I5 CH5 I7
1 1 0 I1 I6 CH6 I7
111I1V
CC
/2 I7
Ref.
Reset
The state of theAnalog Block immediately after RESET is as
follows:
1. The CMPSL Register is set to all zeros
2. The Comparator is disabled
3. The Constant Current Source is disabled
4. CMPNEG is turned off
5. The Port I inputs are electrically isolated from the com-
parator
6. The Capture Timer input is connected to GND
7. CMPISEL0–CMPISEL2 are set to zero
8. All Port I inputs are selected to the default digital input
mode
The comparator outputs have the same specification as
Ports L and G except that the rise and fall times are sym-
metrical.
Interrupts
INTRODUCTION
Each device supports eight vectored interrupts. Interrupt
sources include Timer 0, Timer 1, Timer 2, Timer 3, Port L
Wakeup, Software Trap, MICROWIRE/PLUS, and External
Input.
All interrupts force a branch to location 00FF Hex in program
memory. The VIS instruction may be used to vector to the
appropriate service routine from location 00FF Hex.
The Software trap has the highest priority while the default
VIS has the lowest priority.
Each of the 8 maskable inputs has a fixed arbitration ranking
and vector.
Figure 14
shows the Interrupt Block Diagram.
COP8ACC Family
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Interrupts (Continued)
MASKABLE INTERRUPTS
All interrupts other than the Software Trap are maskable.
Each maskable interrupt has an associated enable bit and
pending flag bit. The pending bit is set to 1 when the interrupt
condition occurs. The state of the interrupt enable bit, com-
bined with the GIE bit determines whether an active pending
flag actually triggers an interrupt. All of the maskable inter-
rupt pending and enable bits are contained in mapped con-
trol registers, and thus can be controlled by the software.
Amaskable interrupt condition triggers an interrupt under the
following conditions:
1. The enable bit associated with that interrupt is set.
2. The GIE bit is set.
3. The devices are not processing a non-maskable inter-
rupt. (If a non-maskable interrupt is being serviced, a
maskable interrupt must wait until that service routine is
completed.)
An interrupt is triggered only when all of these conditions are
met at the beginning of an instruction. If different maskable
interrupts meet these conditions simultaneously, the highest
priority interrupt will be serviced first, and the other pending
interrupts must wait.
Upon Reset, all pending bits, individual enable bits, and the
GIE bit are reset to zero. Thus, a maskable interrupt condi-
tion cannot trigger an interrupt until the program enables it by
setting both the GIE bit and the individual enable bit. When
enabling an interrupt, the user should consider whether or
not a previously activated (set) pending bit should be ac-
knowledged. If, at the time an interrupt is enabled, any pre-
vious occurrences of the interrupt should be ignored, the as-
sociated pending bit must be reset to zero prior to enabling
the interrupt. Otherwise, the interrupt may be simply en-
abled; if the pending bit is already set, it will immediately trig-
ger an interrupt. A maskable interrupt is active if its associ-
ated enable and pending bits are set.
An interrupt is an asychronous event which may occur be-
fore, during, or after an instruction cycle. Any interrupt which
occurs during the execution of an instruction is not acknowl-
edged until the start of the next normally executed instruction
is to be skipped, the skip is performed before the pending in-
terrupt is acknowledged.
At the start of interrupt acknowledgment, the following ac-
tions occur:
1. The GIE bit is automatically reset to zero, preventing any
subsequent maskable interrupt from interrupting the cur-
rent service routine. This feature prevents one maskable
interrupt from interrupting another one being serviced.
2. The address of the instruction about to be executed is
pushed onto the stack.
3. The program counter (PC) is loaded with 00FF Hex,
causing a jump to that program memory location.
The devices require seven instruction cycles to perform the
actions listed above.
If the user wishes to allow nested interrupts, the interrupts
service routine may set the GIE bit to 1 by writing to the PSW
register, and thus allow other maskable interrupts to interrupt
the current service routine. If nested interrupts are allowed,
caution must be exercised. The user must write the program
in such a way as to prevent stack overflow, loss of saved
context information, and other unwanted conditions.
The interrupt service routine stored at location 00FF Hex
should use the VIS instruction to determine the cause of the
interrupt, and jump to the interrupt handling routine corre-
sponding to the highest priority enabled and active interrupt.
Alternately, the user may choose to poll all interrupt pending
DS012865-62
FIGURE 14. Interrupt Block Diagram
COP8ACC Family
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Interrupts (Continued)
and enable bits to determine the source(s) of the interrupt. If
more than one interrupt is active, the user’s program must
decide which interrupt to service.
Within a specific interrupt service routine, the associated
pending bit should be cleared. This is typically done as early
as possible in the service routine in order to avoid missing
the next occurrence of the same type of interrupt event.
Thus, if the same event occurs a second time, even while the
first occurrence is still being serviced, the second occur-
rence will be serviced immediately upon return from the cur-
rent interrupt routine.
An interrupt service routine typically ends with an RETI in-
struction. This instruction sets the GIE bit back to 1, pops the
address stored on the stack, and restores that address to the
program counter. Program execution then proceeds with the
next instruction that would have been executed had there
been no interrupt. If there are any valid interrupts pending,
the highest-priority interrupt is serviced immediately upon re-
turn from the previous interrupt.
VIS INSTRUCTION
The general interrupt service routine, which starts at address
00FF Hex, must be capable of handling all types of inter-
rupts. The VIS instruction, together with an interrupt vector
table, directs the devices to the specific interrupt handling
routine based on the cause of the interrupt.
VIS is a single-byte instruction, typically used at the very be-
ginning of the general interrupt service routine at address
00FF Hex, or shortly after that point, just after the code used
for context switching. The VIS instruction determines which
enabled and pending interrupt has the highest priority, and
causes an indirect jump to the address corresponding to that
interrupt source. The jump addresses (vectors) for all pos-
sible interrupts sources are stored in a vector table.
The vector table may be as long as 32 bytes (maximum of 16
vectors) and resides at the top of the 256-byte block contain-
ing the VIS instruction. However, if the VIS instruction is at
the very top of a 256-byte block (such as at 00FF Hex), the
vector table resides at the top of the next 256-byte block.
Thus, if the VIS instruction is located somewhere between
00FF and 01DF Hex (the usual case), the vector table is lo-
cated between addresses 01E0 and 01FF Hex. If the VIS in-
struction is located between 01FF and 02DF Hex, then the
vector table is located between addresses 02E0 and 02FF
Hex, and so on.
Each vector is 15 bits long and points to the beginning of a
specific interrupt service routine somewhere in the 32 kbyte
memory space. Each vector occupies two bytes of the vector
table, with the higher-order byte at the lower address. The
vectors are arranged in order of interrupt priority. The vector
of the maskable interrupt with the lowest rank is located to
0yE0 (higher-order byte) and 0yE1 (lower-order byte). The
next priority interrupt is located at 0yE2 and 0yE3, and so
forth in increasing rank. The Software Trap has the highest
rank and its vector is always located at 0yFE and 0yFF. The
number of interrupts which can become active defines the
size of the table.
Table 5
shows the types of interrupts, the interrupt arbitration
ranking, and the locations of the corresponding vectors in
the vector table.
The vector table should be filled by the user with the memory
locations of the specific interrupt service routines. For ex-
ample, if the Software Trap routine is located at 0310 Hex,
then the vector location 0yFE and -0yFF should contain the
data 03 and 10 Hex, respectively. When a Software Trap in-
terrupt occurs and the VIS instruction is executed, the pro-
gram jumps to the address specified in the vector table.
The interrupt sources in the vector table are listed in order of
rank, from highest to lowest priority. If two or more enabled
and pending interrupts are detected at the same time, the
one with the highest priority is serviced first. Upon return
from the interrupt service routine, the next highest-level
pending interrupt is serviced.
If the VIS instruction is executed, but no interrupts are en-
abled and pending, the lowest-priority interrupt vector is
used, and a jump is made to the corresponding address in
the vector table. This is an unusual occurrence, and may be
the result of an error. It can legitimately result from a change
in the enable bits or pending flags prior to the execution of
the VIS instruction, such as executing a single cycle instruc-
tion which clears an enable flag at the same time that the
pending flag is set. It can also result, however, from inadvert-
ent execution of the VIS command outside of the context of
an interrupt.
The default VIS interrupt vector can be useful for applica-
tions in which time critical interrupts can occur during the
servicing of another interrupt. Rather than restoring the pro-
gram context (A, B, X, etc.) and executing the RETI instruc-
tion, an interrupt service routine can be terminated by return-
ing to the VIS instruction. In this case, interrupts will be
serviced in turn until no further interrupts are pending and
the default VIS routine is started. After testing the GIE bit to
ensure that execution is not erroneous, the routine should
restore the program context and execute the RETI to return
to the interrupted program.
This technique can save up to fifty instruction cycles (t
c
), or
more, (50µs at 10 MHz oscillator) of latency for pending in-
terrupts with a penalty of fewer than ten instruction cycles if
no further interrupts are pending.
To ensure reliable operation, the user should always use the
VIS instruction to determine the source of an interrupt. Al-
though it is possible to poll the pending bits to detect the
source of an interrupt, this practice is not recommended. The
use of polling allows the standard arbitration ranking to be al-
tered, but the reliability of the interrupt system is compro-
mised. The polling routine must individually test the enable
and pending bits of each maskable interrupt. If a Software
Trap interrupt should occur, it will be serviced last, even
though it should have the highest priority. Under certain con-
ditions, a Software Trap could be triggered but not serviced,
resulting in an inadvertent “locking out” of all maskable inter-
rupts by the Software Trap pending flag. Problems such as
this can be avoided by using VIS instruction.
COP8ACC Family
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Interrupts (Continued)
TABLE 5. Interrupt Vector Table
ARBITRATION SOURCE VECTOR*
RANKING DESCRIPTION ADDRESS
(Hi-Low Byte)
(1) Highest Software INTR Instruction 0yFE–0yFF
(2) Reserved 0yFC–0yFD
(3) External G0 0yFA–0yFB
(4) Timer T0 Idle Timer 0yF8–0yF9
(5) Timer T1 T1A/Underflow 0yF6–0yF7
(6) Timer T1 T1B 0yF4–0yF5
(7) MICROWIRE/PLUS Busy Low 0yF2–0yF3
(8) Reserved 0yF0–0yF1
(9) Reserved 0yEE–0yEF
(10) Reserved 0yEC–0yED
(11) High Speed Capture Timer Capture Overflow/ 0yEA–0yEB
Capture Pending
(12) Reserved 0yE8–0yE9
(13) Reserved 0yE6–0yE7
(14) Reserved 0yE4–0yE5
(15) Port L/Wakeup Port L Edge 0yE2–0yE3
(16) Lowest Default VIS Reserved 0yE0–0yE1
Note 20: *y is a variable which represents the VIS block. VIS and the vector table must be located in the same 256-byte block except if VIS islocated at the last ad-
dress of a block. In this case, the table must be in the next block.
VIS Execution
When the VIS instruction is executed it activates the arbitra-
tion logic. The arbitration logic generates an even number
between E0 and FE (E0, E2, E4, E6 etc...) depending on
which active interrupt has the highest arbitration ranking at
the time of the 1st cycle of VIS is executed. For example, if
the software trap interrupt is active, FE is generated. If the
external interrupt is active and the software trap interrupt is
not, then FAis generated and so forth. If the only active inter-
rupt is software trap, than E0 is generated. This number re-
places the lower byte of the PC. The upper byte of the PC re-
mains unchanged. The new PC is therefore pointing to the
vector of the active interrupt with the highest arbitration rank-
ing. This vector is read from program memory and placed
into the PC which is now pointed to the 1st instruction of the
service routine of the active interrupt with the highest arbitra-
tion ranking.
Figure 15
illustrates the different steps performed by the VIS
instruction.
Figure 16
shows a flowchart for the VIS instruc-
tion.
The non-maskable interrupt pending flag is cleared by the
RPND (Reset Non-Maskable Pending Bit) instruction (under
certain conditions) and upon RESET.
COP8ACC Family
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Interrupts (Continued)
DS012865-65
FIGURE 15. VIS Operation
DS012865-66
FIGURE 16. VIS Flowchart
COP8ACC Family
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Interrupts (Continued)
Programming Example: External Interrupt
PSW =00EF
CNTRL =00EE
RBIT 0,PORTGC
RBIT 0,PORTGD ; G0 pin configured Hi-Z
SBIT IEDG, CNTRL ; Ext interrupt polarity; falling edge
SBIT EXEN, PSW ; Enable the external interrupt
SBIT GIE, PSW ; Set the GIE bit
WAIT: JP WAIT ; Wait for external interrupt
.
.
.
.=0FF ; The interrupt causes a
VIS ; branch to address 0FF
; The VIS causes a branch to
;interrupt vector table
.
.
.
.=01FA ; Vector table (within 256 byte
.ADDRW SERVICE ; of VIS inst.) containing the ext
; interrupt service routine
.
.
INT_EXIT: RETI
.
.
SERVICE: RBIT EXPND, PSW ; Interrupt Service Routine
; Reset ext interrupt pend. bit
.
.
.
JP INT_EXIT ; Return, set the GIE bit
COP8ACC Family
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Interrupts (Continued)
NON-MASKABLE INTERRUPT
Pending Flag
There is a pending flag bit associated with the non-maskable
interrupt, called STPND. This pending flag is not memory-
mapped and cannot be accessed directly by the software.
The pending flag is reset to zero when a device Reset oc-
curs. When the non-maskable interrupt occurs, the associ-
ated pending bit is set to 1. The interrupt service routine
should contain an RPND instruction to reset the pending flag
to zero. The RPND instruction always resets the STPND
flag.
Software Trap
The Software Trap is a special kind of non-maskable inter-
rupt which occurs when the INTR instruction (used to ac-
knowledge interrupts) is fetched from program memory and
placed in the instruction register. This can happen in a vari-
ety of ways, usually because of an error condition. Some ex-
amples of causes are listed below.
If the program counter incorrectly points to a memory loca-
tion beyond the available program memory space, the non-
existent or unused memory location returns zeroes which is
interpreted as the INTR instruction.
If the stack is popped beyond the allowed limit (address 06F
Hex), a 7FFF will be loaded into the PC, if this last location in
program memory is unprogrammed or unavailable, a Soft-
ware Trap will be triggered.
A Software Trap can be triggered by a temporary hardware
condition such as a brownout or power supply glitch.
The Software Trap has the highest priority of all interrupts.
When a Software Trap occurs, the STPND bit is set. The GIE
bit is not affected and the pending bit (not accessible by the
user) is used to inhibit other interrupts and to direct the pro-
gram to the ST service routine with the VIS instruction. Noth-
ing can interrupt a Software Trap service routine except for
another Software Trap. The STPND can be reset only by the
RPND instruction or a chip Reset.
The Software Trap indicates an unusual or unknown error
condition. Generally, returning to normal execution at the
point where the Software Trap occurred cannot be done re-
liably. Therefore, the Software Trap service routine should
reinitialize the stack pointer and perform a recovery proce-
dure that restarts the software at some known point, similar
to a device Reset, but not necessarily performing all the
same functions as a device Reset. The routine must also ex-
ecute the RPND instruction to reset the STPND flag. Other-
wise, all other interrupts will be locked out. To the extent pos-
sible, the interrupt routine should record or indicate the
context of the devices so that the cause of the Software Trap
can be determined.
If the user wishes to return to normal execution from the
point at which the Software Trap was triggered, the user
must first execute RPND, followed by RETSK rather than
RETI or RET. This is because the return address stored on
the stack is the address of the INTR instruction that triggered
the interrupt. The program must skip that instruction in order
to proceed with the next one. Otherwise, an infinite loop of
Software Traps and returns will occur.
Programming a return to normal execution requires careful
consideration. If the Software Trap routine is interrupted by
another Software Trap, the RPND instruction in the service
routine for the second Software Trap will reset the STPND
flag; upon return to the first Software Trap routine, the
STPND flag will have the wrong state. This will allow
maskable interrupts to be acknowledged during the servicing
of the first Software Trap. To avoid problems such as this, the
user program should contain the Software Trap routine to
perform a recovery procedure rather than a return to normal
execution.
Under normal conditions, the STPND flag is reset by a
RPND instruction in the Software Trap service routine. If a
programming error or hardware condition (brownout, power
supply glitch, etc.) sets the STPND flag without providing a
way for it to be cleared, all other interrupts will be locked out.
To alleviate this condition, the user can use extra RPND in-
structions in the main program and in the WATCHDOG ser-
vice routine (if present). There is no harm in executing extra
RPND instructions in these parts of the program.
PORT L INTERRUPTS
Port L provides the user with an additional eight fully select-
able, edge sensitive interrupts which are all vectored into the
same service subroutine.
The interrupt from Port L shares logic with the wake up cir-
cuitry. The register WKEN allows interrupts from Port L to be
individually enabled or disabled. The register WKEDG speci-
fies the trigger condition to be either a positive or a negative
edge. Finally, the register WKPND latches in the pending
trigger conditions.
The GIE (Global Interrupt Enable) bit enables the interrupt
function.
A control flag, LPEN, functions as a global interrupt enable
for Port L interrupts. Setting the LPEN flag will enable inter-
rupts and vice versa. A separate global pending flag is not
needed since the register WKPND is adequate.
Since Port L is also used for waking the devices out of the
HALT or IDLE modes, the user can elect to exit the HALT or
IDLE modes either with or without the interrupt enabled. If he
elects to disable the interrupt, then the devices will restart
execution from the instruction immediately following the in-
struction that placed the microcontroller in the HALT or IDLE
modes. In the other case, the devices will first execute the in-
terrupt service routine and then revert to normal operation.
(See HALT MODE for clock option wakeup information.)
INTERRUPT SUMMARY
The devices use the following types of interrupts, listed be-
low in order of priority:
1. The Software Trap non-maskable interrupt, triggered by
the INTR (00 opcode) instruction. The Software Trap is
acknowledged immediately. This interrupt service rou-
tine can be interrupted only by another Software Trap.
The Software Trap should end with two RPND instruc-
tions followed by a restart procedure.
2. Maskable interrupts, triggered by an on-chip peripheral
block or an external device connected to the device. Un-
der ordinary conditions, a maskable interrupt will not in-
terrupt any other interrupt routine in progress. A
maskable interrupt routine in progress can be inter-
rupted by the non-maskable interrupt request. A
maskable interrupt routine should end with an RETI in-
struction or, prior to restoring context, should return to
execute the VIS instruction. This is particularly useful
when exiting long interrupt service routiness if the time
between interrupts is short. In this case the RETI instruc-
tion would only be executed when the default VIS rou-
tine is reached.
COP8ACC Family
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WATCHDOG
The devices contain a WATCHDOG and clock monitor. The
WATCHDOG is designed to detect the user program getting
stuck in infinite loops resulting in loss of program control or
“runaway” programs. The Clock Monitor is used to detect the
absence of a clock or a very slow clock below a specified
rate on the CKI pin.
The WATCHDOG consists of two independent logic blocks:
WD UPPER and WD LOWER. WD UPPER establishes the
upper limit on the service window and WD LOWER defines
the lower limit of the service window.
Servicing the WATCHDOG consists of writing a specific
value to a WATCHDOG Service Register named WDSVR
which is memory mapped in the RAM. This value is com-
posed of three fields, consisting of a 2-bit Window Select, a
5-bit Key Data field, and the 1-bit Clock Monitor Select field.
Table 6
shows the WDSVR register.
TABLE 6. WATCHDOG Service Register (WDSVR)
Window Key Data Clock
Select Monitor
X X 01100 Y
7 6 54321 0
The lower limit of the service window is fixed at 2048 instruc-
tion cycles. Bits 7 and 6 of the WDSVR register allow the
user to pick an upper limit of the service window.
Table 7
shows the four possible combinations of lower and
upper limits for the WATCHDOG service window. This flex-
ibility in choosing the WATCHDOG service window prevents
any undue burden on the user software.
Bits 5, 4, 3, 2 and 1 of the WDSVR register represent the
5-bit Key Data field. The key data is fixed at 01100. Bit 0 of
the WDSVR Register is the Clock Monitor Select bit.
TABLE 7. WATCHDOG Service Window Select
WDSVR WDSVR Clock Service Window
Bit 7 Bit 6 Monitor (Lower-Upper Limits)
0 0 x 2048–8k t
C
Cycles
0 1 x 2048–16k t
C
Cycles
1 0 x 2048–32k t
C
Cycles
1 1 x 2048–64k t
C
Cycles
x x 0 Clock Monitor Disabled
x x 1 Clock Monitor Enabled
Clock Monitor
The Clock Monitor aboard the devices can be selected or de-
selected under program control. The Clock Monitor is guar-
anteed not to reject the clock if the instruction cycle clock
(1/t
C
) is greater or equal to 10 kHz. This equates to a clock
input rate on CKI of greater or equal to 100 kHz.
WATCHDOG Operation
The WATCHDOG and Clock Monitor are disabled during re-
set. The devices come out of reset with the WATCHDOG
armed, the WATCHDOG Window Select bits (bits 6, 7 of the
WDSVR Register) set, and the Clock Monitor bit (bit 0 of the
WDSVR Register) enabled. Thus, a Clock Monitor error will
occur after coming out of reset, if the instruction cycle clock
frequency has not reached a minimum specified value, in-
cluding the case where the oscillator fails to start.
The WDSVR register can be written to only once after reset
and the key data (bits 5 through 1 of the WDSVR Register)
must match to be a valid write. This write to the WDSVR reg-
ister involves two irrevocable choices: (i) the selection of the
WATCHDOG service window (ii) enabling or disabling of the
Clock Monitor. Hence, the first write to WDSVR Register in-
volves selecting or deselecting the Clock Monitor, select the
WATCHDOG service window and match the WATCHDOG
key data. Subsequent writes to the WDSVR register will
compare the value being written by the user to the WATCH-
DOG service window value and the key data (bits 7 through
1) in the WDSVR Register. Table IX shows the sequence of
events that can occur.
The user must service the WATCHDOG at least once before
the upper limit of the service window expires. The WATCH-
DOG may not be serviced more than once in every lower
limit of the service window. The user may service the
WATCHDOG as many times as wished in the time period be-
tween the lower and upper limits of the service window. The
first write to the WDSVR Register is also counted as a
WATCHDOG service.
The WATCHDOG has an output pin associated with it. This
is the WDOUT pin, on pin 1 of the port G. WDOUT is active
low. The WDOUTpin is in the high impedance state in the in-
active state. Upon triggering the WATCHDOG, the logic will
pull the WDOUT (G1) pin low for an additional 16 t
C
–32 t
C
cycles after the signal level on WDOUT pin goes below the
lower Schmitt trigger threshold. After this delay, the devices
will stop forcing the WDOUT output low. The WATCHDOG
service window will restart when the WDOUT pin goes high.
It is recommended that the user tie the WDOUT pin back to
V
CC
through a resistor in order to pull WDOUT high.
AWATCHDOG service while the WDOUT signal is active will
be ignored. The state of the WDOUT pin is not guaranteed
on reset, but if it powers up low then the WATCHDOG will
time out and WDOUT will enter high impedance state.
The Clock Monitor forces the G1 pin low upon detecting a
clock frequency error. The Clock Monitor error will continue
until the clock frequency has reached the minimum specified
value, after which the G1 output will enter the high imped-
ance TRI-STATE mode following 16 t
C
–32 t
C
clock cycles.
The Clock Monitor generates a continual Clock Monitor error
if the oscillator fails to start, or fails to reach the minimum
specified frequency. The specification for the Clock Monitor
is as follows:
1/t
C
>10 kHz—No clock rejection.
1/t
C
<10 Hz—Guaranteed clock rejection.
WATCHDOG AND CLOCK MONITOR SUMMARY
The following salient points regarding the WATCHDOG and
CLOCK MONITOR should be noted:
•Both the WATCHDOG and CLOCK MONITOR detector
circuits are inhibited during RESET.
•Following RESET, the WATCHDOG and CLOCK MONI-
TOR are both enabled, with the WATCHDOG having the
maximum service window selected.
•The WATCHDOG service window and CLOCK MONI-
TOR enable/disable option can only be changed once,
during the initial WATCHDOG service following RESET.
COP8ACC Family
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WATCHDOG Operation (Continued)
•The initial WATCHDOG service must match the key data
value in the WATCHDOG Service register WDSVR in or-
der to avoid a WATCHDOG error.
•Subsequent WATCHDOG services must match all three
data fields in WDSVR in order to avoid WATCHDOG er-
rors.
•The correct key data value cannot be read from the
WATCHDOG Service register WDSVR. Any attempt to
read this key data value of 01100 from WDSVR will read
as key data value of all 0’s.
•The WATCHDOG detector circuit is inhibited during both
the HALT and IDLE modes.
•The CLOCK MONITOR detector circuit is active during
both the HALT and IDLE modes. Consequently, the de-
vices inadvertently entering the HALT mode will be de-
tected as a CLOCK MONITOR error (provided that the
CLOCK MONITOR enable option has been selected by
the program).
•With the single-pin R/C oscillator mask option selected
and the CLKDLY bit reset, the WATCHDOG service win-
dow will resume following HALT mode from where it left
off before entering the HALT mode.
•With the crystal oscillator mask option selected, or with
the single-pin R/C oscillator mask option selected and the
CLKDLY bit set, the WATCHDOG service window will be
set to its selected value from WDSVR following HALT.
Consequently, the WATCHDOG should not be serviced
for at least 2048 instruction cycles following HALT, but
must be serviced within the selected window to avoid a
WATCHDOG error.
•The IDLE timer T0 is not initialized with RESET.
•The user can sync in to the IDLE counter cycle with an
IDLE counter (T0) interrupt or by monitoring the T0PND
flag. The T0PND flag is set whenever the thirteenth bit of
the IDLE counter toggles (every 4096 instruction cycles).
The user is responsible for resetting the T0PND flag.
•A hardware WATCHDOG service occurs just as the de-
vices exit the IDLE mode. Consequently, the WATCH-
DOG should not be serviced for at least 2048 instruction
cycles following IDLE, but must be serviced within the se-
lected window to avoid a WATCHDOG error.
•Following RESET, the initial WATCHDOG service (where
the service window and the CLOCK MONITOR enable/
disable must be selected) may be programmed any-
where within the maximum service window (65,536 in-
struction cycles) initialized by RESET. Note that this initial
WATCHDOG service may be programmed within the ini-
tial 2048 instruction cycles without causing a WATCH-
DOG error.
TABLE 8. WATCHDOG Service Actions
Key Data Window Data Clock Monitor Action
Match Match Match Valid Service: Restart Service Window
Don’t Care Mismatch Don’t Care Error: Generate WATCHDOG Output
Mismatch Don’t Care Don’t Care Error: Generate WATCHDOG Output
Don’t Care Don’t Care Mismatch Error: Generate WATCHDOG Output
Detection of Illegal Conditions
The devices can detect various illegal conditions resulting
from coding errors, transient noise, power supply voltage
drops, runaway programs, etc.
Reading of undefined ROM gets zeros. The opcode for soft-
ware interrupt is 00. If the program fetches instructions from
undefined ROM, this will force a software interrupt, thus sig-
naling that an illegal condition has occurred.
The subroutine stack grows down for each call (jump to sub-
routine), interrupt, or PUSH, and grows up for each return or
POP.The stack pointer is initialized to RAM location 06F Hex
during reset. Consequently, if there are more returns than
calls, the stack pointer will point to addresses 070 and 071
Hex (which are undefined RAM). Undefined RAM from ad-
dresses 070 to 07F (Segment 0), and all other segments
(i.e., Segments 4... etc.) is read as all 1’s, which in turn will
cause the program to return to address 7FFF Hex. This is an
undefined ROM location and the instruction fetched (all 0’s)
from this location will generate a software interrupt signaling
an illegal condition.
Thus, the chip can detect the following illegal conditions:
1. Executing from undefined ROM
2. Over “POP”ing the stack by having more returns than
calls.
When the software interrupt occurs, the user can re-initialize
the stack pointer and do a recovery procedure before restart-
ing (this recovery program is probably similar to that follow-
ing reset, but might not contain the same program initializa-
tion procedures). The recovery program should reset the
software interrupt pending bit using the RPND instruction.
MICROWIRE/PLUS
MICROWIRE/PLUS is a serial synchronous communications
interface. The MICROWIRE/PLUS capability enables the de-
vices to interface with any of National Semiconductor’s
MICROWIRE peripherals (i.e. A/D converters, display driv-
ers, E2PROMs etc.) and with other microcontrollers which
support the MICROWIRE interface. It consists of an 8-bit se-
rial shift register (SIO) with serial data input (SI), serial data
output (SO) and serial shift clock (SK).
Figure 17
shows a
block diagram of the MICROWIRE/PLUS logic.
The shift clock can be selected from either an internal source
or an external source. Operating the MICROWIRE/PLUS ar-
rangement with the internal clock source is called the Master
mode of operation. Similarly, operating the MICROWIRE/
PLUS arrangement with an external shift clock is called the
Slave mode of operation.
The CNTRL register is used to configure and control the
MICROWIRE/PLUS mode. To use the MICROWIRE/PLUS,
the MSEL bit in the CNTRLregister is set to one. In the mas-
ter mode, the SK clock rate is selected by the two bits, SL0
and SL1, in the CNTRL register.
Table 9
details the different
clock rates that may be selected.
COP8ACC Family
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MICROWIRE/PLUS (Continued)
TABLE 9. MICROWIRE/PLUS Master Mode Clock Select
SL1 SL0 SK period
0 0 2Xt
C
0 1 4Xt
C
1 x 8Xt
C
Where t
C
is the instruction cycle clock
MICROWIRE/PLUS OPERATION
Setting the BUSY bit in the PSW register causes the
MICROWIRE/PLUS to start shifting the data. It gets reset
when eight data bits have been shifted. The user may reset
the BUSY bit by software to allow less than 8 bits to shift. If
enabled, an interrupt is generated when eight data bits have
been shifted. The devices may enter the MICROWIRE/PLUS
mode either as a Master or as a Slave.
Figure 18
shows how
two devices, microcontrollers and several peripherals may
be interconnected using the MICROWIRE/PLUS
arrangements.
WARNING
The SIO register should only be loaded when the SK clock is
low. Loading the SIO register while the SK clock is high will
result in undefined data in the SIO register. SK clock is nor-
mally low when not shifting.
Setting the BUSY flag when the input SK clock is high in the
MICROWIRE/PLUS slave mode may cause the current SK
clock for the SIO shift register to be narrow. For safety, the
BUSY flag should only be set when the input SK clock is low.
MICROWIRE/PLUS Master Mode Operation
In the MICROWIRE/PLUS Master mode of operation the
shift clock (SK) is generated internally. The MICROWIRE
Master always initiates all data exchanges. The MSEL bit in
the CNTRL register must be set to enable the SO and SK
functions onto the G Port. The SO and SK pins must also be
selected as outputs by setting appropriate bits in the Port G
configuration register.
Table 10
summarizes the bit settings
required for Master mode of operation.
MICROWIRE/PLUS Slave Mode Operation
In the MICROWIRE/PLUS Slave mode of operation the SK
clock is generated by an external source. Setting the MSEL
bit in the CNTRL register enables the SO and SK functions
onto the G Port. The SK pin must be selected as an input
and the SO pin is selected as an output pin by setting and re-
setting the appropriate bits in the Port G configuration regis-
ter. Table XI summarizes the settings required to enter the
Slave mode of operation.
The user must set the BUSY flag immediately upon entering
the Slave mode. This will ensure that all data bits sent by the
Master will be shifted properly. After eight clock pulses the
BUSY flag will be cleared and the sequence may be re-
peated.
TABLE 10. MICROWIRE/PLUS Mode Settings
This table assumes that the control flag MSEL is set.
G4 (SO) G5 (SK) G4 G5 Operation
Config. Bit Config. Bit Fun. Fun.
1 1 SO Int. MICROWIRE/PLUS
SK Master
0 1 TRI- Int. MICROWIRE/PLUS
STATE SK Master
1 0 SO Ext. MICROWIRE/PLUS
SK Slave
0 0 TRI- Ext. MICROWIRE/PLUS
STATE SK Slave
Alternate SK Phase Operation
The devices allow either the normal SK clock or an alternate
phase SK clock to shift data in and out of the SIO register. In
both the modes the SK is normally low. In the normal mode
data is shifted in on the rising edge of the SK clock and the
data is shifted out on the falling edge of the SK clock. The
SIO register is shifted on each falling edge of the SK clock.
In the alternate SK phase operation, data is shifted in on the
falling edge of the SK clock and shifted out on the rising edge
of the SK clock.
A control flag, SKSEL, allows either the normal SK clock or
the alternate SK clock to be selected. Resetting SKSEL
causes the MICROWIRE/PLUS logic to be clocked from the
normal SK signal. Setting the SKSEL flag selects the alter-
nate SK clock. The SKSEL is mapped into the G6 configura-
tion bit. The SKSEL flag will power up in the reset condition,
selecting the normal SK signal.
DS012865-63
FIGURE 17. MICROWIRE/PLUS Block Diagram
COP8ACC Family
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MICROWIRE/PLUS (Continued)
DS012865-64
FIGURE 18. MICROWIRE/PLUS Application
COP8ACC Family
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Memory Map
All RAM, ports and registers (except A and PC) are mapped
into data memory address space.
Address Contents
S/ADD REG
0000 to 006F On-Chip RAM bytes (112
bytes)
0070 to 007F Unused RAM Address Space
(Reads As All Ones)
xx80 to xxAF Unused RAM Address Space
(Reads Undefined Data)
xxB0 Reserved
XXB1 Reserved
xxB2 Reserved
xxB3 Reserved
xxB4 Reserved
xxB5 Reserved
xxB6 Reserved
xxB7 Comparator Select Register
(CMPSL)
xxB8 to xxBF Reserved
xxC0 Reserved
xxC1 Reserved
xxC2 Reserved
xxC3 Reserved
xxC4 Reserved
xxC5 Reserved
xxC6 Reserved
xxC7 WATCHDOG Service Register
(Reg:WDSVR)
xxC8 MIWU Edge Select Register
(Reg:WKEDG)
xxC9 MIWU Enable Register
(Reg:WKEN)
xxCA MIWU Pending Register
(Reg:WKPND)
xxCB Reserved
xxCC CAPTLO (Capture Timer
Low-Byte)
xxCD CAPTHI (Capture Timer
High-Byte)
xxCE CAPCNTL (Capture Timer
Control Register)
xxCF Idle Timer Control Register
xxD0 Port L Data Register
xxD1 Port L Configuration Register
xxD2 Port L Input Pins (Read Only)
xxD3 Reserved
xxD4 Port G Data Register
xxD5 Port G Configuration Register
xxD6 Port G Input Pins (Read Only)
xxD7 Port I Input Pins (Read Only)
xxD8 Reserved
Address Contents
S/ADD REG
xxD9 Reserved
xxDA Reserved
xxDB Reserved
xxDC Port D
xxDD to DF Reserved
xxE0 to xxE5 Reserved
xxE6 Timer T1 Autoload Register
T1RB Lower Byte
xxE7 Timer T1 Autoload Register
T1RB Upper Byte
xxE8 ICNTRL Register
xxE9 MICROWIRE/PLUS Shift
Register
xxEA Timer T1 Lower Byte
xxEB Timer T1 Upper Byte
xxEC Timer T1 Autoload Register
T1RA Lower Byte
xxED Timer T1 Autoload Register
T1RA Upper Byte
xxEE CNTRL Control Register
xxEF PSW Register
xxF0 to xxFB On-Chip RAM Mapped as
Registers
xxFC X Register
xxFD SP Register
xxFE B Register
xxFF Reserved
0100-017F Reserved
Reading memory locations 0070H-007FH (Segment 0) will
return all ones. Reading unused memory locations
0080H-00AFH (Segment 0) will return undefined data. Read-
ing memory locations from other Segments (i.e., Segment 2,
Segment 3,…etc.) will return undefined data.
Addressing Modes
There are ten addressing modes, six for operand addressing
and four for transfer of control.
OPERAND ADDRESSING MODES
Register Indirect
This is the “normal” addressing mode. The operand is the
data memory addressed by the B pointer or X pointer.
Register Indirect (with auto post increment or decre-
ment of pointer)
This addressing mode is used with the LD and X instruc-
tions. The operand is the data memory addressed by the B
pointer or X pointer. This is a register indirect mode that au-
tomatically post increments or decrements the B or X regis-
ter after executing the instruction.
Direct
The instruction contains an 8-bit address field that directly
points to the data memory for the operand.
COP8ACC Family
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Addressing Modes (Continued)
Immediate
The instruction contains an 8-bit immediate field as the oper-
and.
Short Immediate
This addressing mode is used with the Load B Immediate in-
struction. The instruction contains a 4-bit immediate field as
the operand.
Indirect
This addressing mode is used with the LAID instruction. The
contents of the accumulator are used as a partial address
(lower 8 bits of PC) for accessing a data operand from the
program memory.
TRANSFER OF CONTROL ADDRESSING MODES
Relative
This mode is used for the JP instruction, with the instruction
field being added to the program counter to get the new pro-
gram location. JP has a range from −31 to +32 to allow a
1-byte relative jump (JP + 1 is implemented by a NOP in-
struction). There are no “pages” when using JP, since all 15
bits of PC are used.
Absolute
This mode is used with the JMP and JSR instructions, with
the instruction field of 12 bits replacing the lower 12 bits of
the program counter (PC). This allows jumping to any loca-
tion in the current 4k program memory segment.
Absolute Long
This mode is used with the JMPLand JSRL instructions, with
the instruction field of 15 bits replacing the entire 15 bits of
the program counter (PC). This allows jumping to any loca-
tion up to 32k in the program memory space.
Indirect
This mode is used with the JID instruction. The contents of
the accumulator are used as a partial address (lower 8 bits of
PC) for accessing a location in the program memory. The
contents of this program memory location serve as a partial
address (lower 8 bits of PC) for the jump to the next instruc-
tion.
Note: The VIS is a special case of the Indirect Transfer of Control addressing
mode, where the double byte vector associated with the interrupt is
transferred from adjacent addresses in the program memory into the
program counter (PC) in order to jump to the associated interrupt ser-
vice routine.
Instruction Set
Register and Symbol Definition
Registers
A 8-Bit Accumulator Register
B 8-Bit Address Register
X 8-Bit Address Register
SP 8-Bit Stack Pointer Register
PC 15-Bit Program Counter Register
PU Upper 7 Bits of PC
PL Lower 8 Bits of PC
C 1-Bit of PSW Register for Carry
HC 1-Bit of PSW Register for Half Carry
GIE 1-Bit of PSW Register for Global Interrupt
Enable
VU Interrupt Vector Upper Byte
VL Interrupt Vector Lower Byte
Symbols
[B] Memory Indirectly Addressed by B Register
[X] Memory Indirectly Addressed by X Register
MD Direct Addressed Memory
Mem Direct Addressed Memory or [B]
Meml Direct Addressed Memory or [B] or Immediate
Data
Imm 8-Bit Immediate Data
Reg Register Memory: Addresses F0 to FF
(Includes B, X and SP)
Bit Bit Number (0 to 7)
←Loaded with
↔Exchanged with
INSTRUCTION SET
ADD A,Meml ADD A ←A + Meml
ADC A,Meml ADD with Carry A ←A+Meml+C,C←Carry, HC ←Half Carry
SUBC A,Meml Subtract with Carry A ←A−MemI+C,C←Carry, HC ←Half Carry
AND A,Meml Logical AND A ←A and Meml
ANDSZ A,Imm Logical AND Immed., Skip if Zero Skip next if (A and Imm) = 0
OR A,Meml Logical OR A ←A or Meml
XOR A,Meml Logical EXclusive OR A ←A xor Meml
IFEQ MD,Imm IF EQual Compare MD and Imm, Do next if MD = Imm
IFEQ A,Meml IF EQual Compare A and Meml, Do next if A = Meml
IFNE A,Meml IF Not Equal Compare A and Meml, Do next if A ≠Meml
IFGT A,Meml IF Greater Than Compare A and Meml, Do next if A >Meml
IFBNE #If B Not Equal Do next if lower 4 bits of B ≠Imm
DRSZ Reg Decrement Reg., Skip if Zero Reg ←Reg − 1, Skip if Reg = 0
COP8ACC Family
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Instruction Set (Continued)
SBIT #,Mem Set BIT 1 to bit, Mem (bit = 0 to 7 immediate)
RBIT #,Mem Reset BIT 0 to bit, Mem
IFBIT #,Mem IF BIT If bit #,A or Mem is true do next instruction
RPND Reset PeNDing Flag Reset Software Interrupt Pending Flag
X A,Mem EXchange A with Memory A ↔Mem
X A,[X] EXchange A with Memory [X] A ↔[X]
LD A,Meml LoaD A with Memory A ←Meml
LD A,[X] LoaD A with Memory [X] A ←[X]
LD B,Imm LoaD B with Immed. B ←Imm
LD Mem,Imm LoaD Memory Immed Mem ←Imm
LD Reg,Imm LoaD Register Memory Immed. Reg ←Imm
XA,[B
±
] EXchange A with Memory [B] A ↔[B], (B ←B±1)
XA,[X
±
] EXchange A with Memory [X] A ↔[X], (X ←X±1)
LD A, [B±] LoaD A with Memory [B] A ←[B], (B ←B±1)
LD A, [X±] LoaD A with Memory [X] A ←[X], (X ←X±1)
LD [B±],Imm LoaD Memory [B] Immed. [B] ←Imm, (B ←B±1)
CLR A CLeaR A A ←0
INC A INCrement A A ←A+1
DEC A DECrement A A ←A−1
LAID Load A InDirect from ROM A ←ROM (PU,A)
DCOR A Decimal CORrect A A ←BCD correction of A (follows ADC, SUBC)
RRC A Rotate A Right thru C C →A7 →... →A0 →C
RLC A Rotate A Left thru C C ←A7 ←... ←A0 ←C
SWAP A SWAP nibbles of A A7...A4 ↔A3...A0
SC Set C C ←1, HC ←1
RC Reset C C ←0, HC ←0
IFC IF C IF C is true, do next instruction
IFNC IF Not C If C is not true, do next instruction
POP A POP the stack into A SP ←SP+1,A←[SP]
PUSH A PUSH A onto the stack [SP] ←A, SP ←SP−1
VIS Vector to Interrupt Service Routine PU ←[VU], PL←[VL]
JMPL Addr. Jump absolute Long PC ←ii (ii = 15 bits, 0 to 32k)
JMP Addr. Jump absolute PC9...0 ←i (i = 12 bits)
JP Disp. Jump relative short PC ←PC+r(ris−31to+32, except 1)
JSRL Addr. Jump SubRoutine Long [SP]←PL, [SP-1] ←PU,SP-2, PC ←ii
JSR Addr Jump SubRoutine [SP]←PL, [SP-1] ←PU,SP-2, PC9...0 ←i
JID Jump InDirect PL←ROM (PU,A)
RET RETurn from subroutine SP + 2, PL←[SP], PU←[SP-1]
RETSK RETurn and SKip SP + 2, PL←[SP],PU←[SP-1], skip next instruction
RETI RETurn from Interrupt SP + 2, PL ←[SP],PU←[SP-1],GIE←1
INTR Generate an Interrupt [SP]←PL, [SP-1]←PU, SP-2, PC←0FF
NOP No OPeration PC←PC+1
COP8ACC Family
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Instruction Set (Continued)
Instruction Execution Time
Most instructions are single byte (with immediate addressing
mode instructions taking two bytes).
Most single byte instructions take one cycle time to execute.
Skipped instructions require x number of cycles to be
skipped, where x equals the number of bytes in the skipped
instruction opcode.
See the BYTES and CYCLES per INSTRUCTION table for
details.
Bytes and Cycles per Instruction
The following table shows the number of bytes and cycles for
each instruction in the format of byte/cycle.
Arithmetic and Logic Instructions
[B] Direct Immed
ADD 1/1 3/4 2/2
ADC 1/1 3/4 2/2
SUBC 1/1 3/4 2/2
AND 1/1 3/4 2/2
OR 1/1 3/4 2/2
XOR 1/1 3/4 2/2
IFEQ 1/1 3/4 2/2
IFGT 1/1 3/4 2/2
IFBNE 1/1
DRSZ 1/1 1/3
SBIT 1/1 3/4
RBIT 1/1 3/4
IFBIT 1/1 3/4
RPND 1/1
Instructions Using A and C
CLRA 1/1
INCA 1/1
DECA 1/1
LAID 1/3
DCORA 1/1
RRCA 1/1
RLCA 1/1
SWAPA 1/1
SC 1/1
RC 1/1
IFC 1/1
IFNC 1/1
PUSHA 1/3
POPA 1/3
ANDSZ 2/2
Transfer of Control Instructions
JMPL 3/4
JMP 2/3
JP 1/3
JSRL 3/5
JSR 2/5
JID 1/3
VIS 1/5
RET 1/5
RETSK 1/5
RETI 1/5
INTR 1/7
NOP 1/1
Memory Transfer Instructions
Register Direct Immed. Register Indirect
Indirect Auto Incr and Decr
[B] [X] [B+, B−] [X+, X−]
X A, (Note 21) 1/1 1/3 2/3 1/2 1/3
LD A, (Note 21) 1/1 1/3 2/3 2/2 1/2 1/3
LD B,Imm 1/1 (If B <16)
LD B,Imm 2/2 (If B >15)
LD Mem,Imm 2/2 3/3 2/2
LD Reg,Imm 2/3
IFEQ MD,Imm 3/3
Note 21: Memory location addressed by B or X or directly.
COP8ACC Family
www.national.com35
Instruction Set (Continued)
Opcode Table
UPPER NIBBLE
F E D C BA9 876 5 4 3 2 10
LOWER NIBBLE
JP−15 JP−31 LD 0F0,#i DRSZ
0F0 RRCA RC ADC
A,#iADC
A,[B] IFBIT
0,[B] ANDSZ
A,#iLD
B,#0F IFBNE 0 JSR
x000–x0FF JMP
x000–x0FF JP+17 INTR 0
JP−14 JP−30 LD 0F1,#i DRSZ
0F1 *SC SUBC
A,#iSUBC
A,[B] IFBIT
1,[B] *LD
B,#0E IFBNE 1 JSR
x100–x1FF JMP
x100–x1FF JP+18 JP+2 1
JP−13 JP−29 LD 0F2,#i DRSZ
0F2 X
A,[X+] X
A,[B+] IFEQ
A,#iIFEQ
A,[B] IFBIT
2,[B] *LD
B,#0D IFBNE 2 JSR
x200–x2FF JMP
x200–x2FF JP+19 JP+3 2
JP−12 JP−28 LD 0F3,#i DRSZ
0F3 X
A,[X−] X
A,[B−] IFGT
A,#iIFGT
A,[B] IFBIT
3,[B] *LD
B,#0C IFBNE 3 JSR
x300–x3FF JMP
x300–x3FF JP+20 JP+4 3
JP−11 JP−27 LD 0F4,#i DRSZ
0F4 VIS LAID ADD
A,#iADD
A,[B] IFBIT
4,[B] CLRA LD
B,#0B IFBNE 4 JSR
x400–x4FF JMP
x400–x4FF JP+21 JP+5 4
JP−10 JP−26 LD 0F5,#i DRSZ
0F5 RPND JID AND
A,#iAND
A,[B] IFBIT
5,[B] SWAPA LD
B,#0A IFBNE 5 JSR
x500–x5FF JMP
x500–x5FF JP+22 JP+6 5
JP−9 JP−25 LD 0F6,#i DRSZ
0F6 X A,[X] X
A,[B] XOR
A,#iXOR
A,[B] IFBIT
6,[B] DCORA LD
B,#09 IFBNE 6 JSR
x600–x6FF JMP
x600–x6FF JP+23 JP+7 6
JP−8 JP−24 LD 0F7,#i DRSZ
0F7 **
OR
A,#iOR
A,[B] IFBIT
7,[B] PUSHA LD
B,#08 IFBNE 7 JSR
x700–x7FF JMP
x700–x7FF JP+24 JP+8 7
JP−7 JP−23 LD 0F8,#i DRSZ
0F8 NOP RLCA LD A,#i IFC SBIT
0,[B] RBIT
0,[B] LD
B,#07 IFBNE 8 JSR
x800–x8FF JMP
x800–x8FF JP+25 JP+9 8
JP−6 JP−22 LD 0F9,#i DRSZ
0F9 IFNE
A,[B] IFEQ
Md,#iIFNE
A,#iIFNC SBIT
1,[B] RBIT
1,[B] LD
B,#06 IFBNE 9 JSR
x900–x9FF JMP
x900–x9FF JP+26 JP+10 9
JP−5 JP−21 LD 0FA,#i DRSZ
0FA LD
A,[X+] LD
A,[B+] LD
[B+],#iINCA SBIT
2,[B] RBIT
2,[B] LD
B,#05 IFBNE 0A JSR
xA00–xAFF JMP
xA00–xAFF JP+27 JP+11 A
JP−4 JP−20 LD 0FB,#i DRSZ
0FB LD
A,[X−] LD
A,[B−] LD
[B−],#iDECA SBIT
3,[B] RBIT
3,[B] LD
B,#04 IFBNE 0B JSR
xB00–xBFF JMP
xB00–xBFF JP+28 JP+12 B
JP−3 JP−19 LD 0FC,#i DRSZ
0FC LD
Md,#iJMPL X A,Md POPA SBIT
4,[B] RBIT
4,[B] LD
B,#03 IFBNE 0C JSR
xC00–xCFF JMP
xC00–xCFF JP+29 JP+13 C
JP−2 JP−18 LD 0FD,#i DRSZ
0FD DIR JSRL LD
A,Md RETSK SBIT
5,[B] RBIT
5,[B] LD
B,#02 IFBNE 0D JSR
xD00–xDFF JMP
xD00–xDFF JP+30 JP+14 D
JP−1 JP−17 LD 0FE,#i DRSZ
0FE LD
A,[X] LD
A,[B] LD
[B],#iRET SBIT
6,[B] RBIT
6,[B] LD
B,#01 IFBNE 0E JSR
xE00–xEFF JMP
xE00–xEFF JP+31 JP+15 E
JP−0 JP−16 LD 0FF,#i DRSZ
0FF **
LD B,#i RETI SBIT
7,[B] RBIT
7,[B] LD
B,#00 IFBNE 0F JSR
xF00–xFFF JMP
xF00–xFFF JP+32 JP+16 F
where,
i is the immediate data
Md is a directly addressed memory location
*is an unused opcode
The opcode 60 Hex is also the opcode for IFBIT #i,A
COP8ACC Family
www.national.com 36
Mask Options
The mask programmable options are shown below. The op-
tions are programmed at the same time as the ROM pattern
submission.
OPTION 1: CLOCK CONFIGURATION (Crystal
Oscillator is selected via the -XE suffix
for COP8ACC7)
= 1 Crystal Oscillator (CKI/10)
G7 (CKO) is clock generator output
to crystal/resonator CKI is the
clock input
= 2 Single-pin RC controlled oscillator
(CKI/10)
G7 is available as a HALT restart
and/or general purpose input
OPTION 2: HALT (HALT mode is enabled on
COP8ACC7)
= 1 Enable HALT mode
= 2 Disable HALT mode
OPTION 3: BONDING OPTIONS (Selected by
package selection on COP8ACC7)
= 1 28-Pin DIP
= 2 28-Pin SO
= 3 N/A
= 4 20-Pin SO
Development Tools Support
OVERVIEW
National is engaged with an international community of inde-
pendent 3rd party vendors who provide hardware and soft-
ware development tool support. Through National’s interac-
tion and guidance, these tools cooperate to form a choice of
solutions that fits each developer’s needs.
This section provides a summary of the tool and develop-
ment kits currently available. Up-to-date information, selec-
tion guides, free tools, demos, updates, and purchase infor-
mation can be obtained at our web site at:
www.national.com/cop8.
SUMMARY OF TOOLS
COP8 Evaluation Tools
•COP8–NSEVAL: Free Software Evaluation package for
Windows. A fully integrated evaluation environment for
COP8, including versions of WCOP8 IDE (Integrated De-
velopment Environment), COP8-NSASM, COP8-MLSIM,
COP8C, DriveWay™COP8, Manuals, and other COP8
information.
•COP8–MLSIM: Free Instruction Level Simulator tool for
Windows. For testing and debugging software instruc-
tions only (No I/O or interrupt support).
•COP8–EPU: Very Low cost COP8 Evaluation & Pro-
gramming Unit. Windows based evaluation and
hardware-simulation tool, with COP8 device programmer
and erasable samples. Includes COP8-NSDEV, Drive-
way COP8 Demo, MetaLink Debugger, I/O cables and
power supply.
•COP8–EVAL-ICUxx: Very Low cost evaluation and de-
sign test board for COP8ACC and COP8SGx Families,
from ICU. Real-time environment with add-on A/D, D/A,
and EEPROM. Includes software routines and reference
designs.
•Manuals,Applications Notes, Literature:Available free
from our web site at: www.national.com/cop8.
COP8 Integrated Software/Hardware Design Develop-
ment Kits
•COP8-EPU: Very Low cost Evaluation & Programming
Unit. Windows based development and hardware-
simulation tool for COPSx/xG families, with COP8 device
programmer and samples. Includes COP8-NSDEV,
Driveway COP8 Demo, MetaLink Debugger, cables and
power supply.
•COP8-DM: Moderate cost Debug Module from MetaLink.
A Windows based, real-time in-circuit emulation tool with
COP8 device programmer. Includes COP8-NSDEV,
DriveWay COP8 Demo, MetaLink Debugger, power sup-
ply, emulation cables and adapters.
COP8 Development Languages and Environments
•COP8-NSASM: Free COP8 Assembler v5 for Win32.
Macro assembler, linker, and librarian for COP8 software
development. Supports all COP8 devices. (DOS/Win16
v4.10.2 available with limited support). (Compatible with
WCOP8 IDE, COP8C, and DriveWay COP8).
•COP8-NSDEV: Very low cost Software Development
Package for Windows. An integrated development envi-
ronment for COP8, including WCOP8 IDE, COP8-
NSASM, COP8-MLSIM.
•COP8C: Moderately priced C Cross-Compiler and Code
Development System from Byte Craft (no code limit). In-
cludes BCLIDE (Byte Craft Limited Integrated Develop-
ment Environment) for Win32, editor, optimizing C Cross-
Compiler, macro cross assembler, BC-Linker, and
MetaLink tools support. (DOS/SUN versions available;
Compiler is installable under WCOP8 IDE; Compatible
with DriveWay COP8).
•EWCOP8-KS: Very Low cost ANSI C-Compiler and Em-
bedded Workbench from IAR (Kickstart version:
COP8Sx/Fx only with 2k code limit; No FP). A fully inte-
grated Win32 IDE, ANSI C-Compiler, macro assembler,
editor, linker, Liberian, C-Spy simulator/debugger, PLUS
MetaLink EPU/DM emulator support.
•EWCOP8-AS: Moderately priced COP8 Assembler and
Embedded Workbench from IAR (no code limit).Afully in-
tegrated Win32 IDE, macro assembler, editor, linker, li-
brarian, and C-Spy high-level simulator/debugger with
I/O and interrupts support. (Upgradeable with optional
C-Compiler and/or MetaLink Debugger/Emulator sup-
port).
•EWCOP8-BL: Moderately priced ANSI C-Compiler and
Embedded Workbench from IAR (Baseline version: All
COP8 devices; 4k code limit; no FP). A fully integrated
Win32 IDE, ANSI C-Compiler, macro assembler, editor,
linker, librarian, and C-Spy high-level simulator/debugger.
(Upgradeable; CWCOP8-M MetaLink tools interface sup-
port optional).
•EWCOP8: Full featured ANSI C-Compiler and Embed-
ded Workbench for Windows from IAR (no code limit). A
fully integrated Win32 IDE, ANSI C-Compiler, macro as-
sembler, editor, linker, librarian, and C-Spy high-level
simulator/debugger. (CWCOP8-M MetaLink tools inter-
face support optional).
•EWCOP8-M: Full featuredANSI C-Compiler and Embed-
ded Workbench for Windows from IAR (no code limit). A
fully integrated Win32 IDE, ANSI C-Compiler, macro as-
sembler, editor, linker, librarian, C-Spy high-level
simulator/debugger, PLUS MetaLink debugger/hardware
interface (CWCOP8-M).
COP8ACC Family
www.national.com37
Development Tools Support
(Continued)
COP8 Productivity Enhancement Tools
•WCOP8 IDE: Very Low cost IDE (Integrated Develop-
ment Environment) from KKD. Supports COP8C, COP8-
NSASM, COP8-MLSIM, DriveWay COP8, and MetaLink
debugger under a common Windows Project Manage-
ment environment. Code development, debug, and emu-
lation tools can be launched from the project window
framework.
•DriveWay-COP8: Low cost COP8 Peripherals Code
Generation tool from Aisys Corporation. Automatically
generates tested and documented C or Assembly source
code modules containing I/O drivers and interrupt han-
dlers for each on-chip peripheral. Application specific
code can be inserted for customization using the inte-
grated editor. (Compatible with COP8-NSASM, COP8C,
and WCOP8 IDE.)
•COP8-UTILS: Free set of COP8 assembly code ex-
amples, device drivers, and utilities to speed up code de-
velopment.
•COP8-MLSIM: Free Instruction Level Simulator tool for
Windows. For testing and debugging software instruc-
tions only (No I/O or interrupt support).
COP8 Real-Time Emulation Tools
•COP8-DM: MetaLink Debug Module. A moderately
priced real-time in-circuit emulation tool, with COP8 de-
vice programmer. Includes COP8-NSDEV, DriveWay
COP8 Demo, MetaLink Debugger, power supply, emula-
tion cables and adapters.
•IM-COP8: MetaLink iceMASTER®. A full featured, real-
time in-circuit emulator for COP8 devices. Includes Met-
aLink Windows Debugger, and power supply. Package-
specific probes and surface mount adaptors are ordered
separately.
COP8 Device Programmer Support
•MetaLink’s EPU and Debug Module include development
device programming capability for COP8 devices.
•Third-party programmers and automatic handling equip-
ment cover needs from engineering prototype and pilot
production, to full production environments.
•Factory programming available for high-volume require-
ments.
TOOLS ORDERING NUMBERS FOR THE COP8ACC5 FAMILY DEVICES
Vendor Tools Order Number Cost Notes
National COP8-NSEVAL COP8-NSEVAL Free Web site download
COP8-NSASM COP8-NSASM Free Included in EPU and DM. Web site download
COP8-MLSIM COP8-MLSIM Free Included in EPU and DM. Web site download
COP8-NSDEV COP8-NSDEV VL Included in EPU and DM. Order CD from website
COP8-EPU Not available for this device
COP8-DM Contact MetaLink
Development
Devices COP8ACC7 VL 16k OTP devices; 20/28 pin.
OTP
Programming
Adapters
PN# EDI 28D
(SO)/40D-Z-COP8LXC L For programming 20/28 SOIC and DIP on any
programmer.
IM-COP8 Contact MetaLink
COP8-EPU Not available for this device
COP8-DM DM4-COP8-ACx (10
MHz), plus PS-10, plus
DM-COP8/xxx (ie. 28D)
M Included p/s (PS-10), target cable of choice (DIP or
PLCC; i.e. DM-COP8/28D), EDI programming sockets.
Add target adapter (if needed)
DM Target
Adapters MHW-CNV38 or 39 L DM target converters for 20SO or 28SO; (i.e.
MHW-CNV38 for 20 pin DIP to SO package converter)
OTP
Programming
Adapters
PN# EDI 28D
(SO)/40D-Z-COP8LXC L For programming 20/28 SOIC and DIP on any
programmer.
IM-COP8 IM-COP8-AD-464 (-220)
(10 MHz maximum) H Base unit 10 MHz; -220 = 220V; add probe card
(required) and target adapter (if needed); included
software and manuals
PC-8AC28DW-AD-10 M 10 MHz 20/28 DIP probe card; 2.5V to 5.5V
IM Probe Target
Adapter MHW-SOIC28 L 28 pin SOIC adapter for probe card
ICU COP8-EVAL COP8-EVAL_ICUAC L No poweer supply
KKD WCOP8-IDE WCOP8-IDE VL Included in EPU and DM
IAR EWCOP8-xx See summary above L - H Included all software and manuals
COP8ACC Family
www.national.com 38
Development Tools Support (Continued)
Byte
Craft COP8C COP8C M Included all software and manuals
Aisys DriveWay COP8 DriveWay COP8 L Included all software and manuals
OTP Programmers Contact vendors L - H For approved programmer listings and vendor
information, go to our OTP support page at:
www.national.com/cop8
Cost: Free; VL =<$100; L = $100 - $300; M = $300 - $1k; H = $1k - $3k; VH = $3k - $5k
WHERE TO GET TOOLS
Tools are ordered directly from the following vendors. Please go to the vendor’s web site for current listings of distributors.
Vendor Home Office Electronic Sites Other Main Offices
Aisys U.S.A.: Santa Clara, CA www.aisysinc.com Distributors
1-408-327-8820 info@aisysinc.com
fax: 1-408-327-8830
Byte Craft U.S.A. www.bytecraft.com Distributors
1-519-888-6911 info@bytecraft.com
fax: 1-519-746-6751
IAR Sweden: Uppsala www.iar.se U.S.A.: San Francisco
+46 18 16 78 00 info@iar.se 1-415-765-5500
fax: +46 18 16 78 38 info@iar.com fax: 1-415-765-5503
info@iarsys.co.uk U.K.: London
info@iar.de +44 171 924 33 34
fax: +44 171 924 53 41
Germany: Munich
+49 89 470 6022
fax: +49 89 470 956
ICU Sweden: Polygonvaegen www.icu.se Switzeland: Hoehe
+46 8 630 11 20 support@icu.se +41 34 497 28 20
fax: +46 8 630 11 70 support@icu.ch fax: +41 34 497 28 21
KKD Denmark: www.kkd.dk
MetaLink U.S.A.: Chandler, AZ www.metaice.com Germany: Kirchseeon
1-800-638-2423 sales@metaice.com 80-91-5696-0
fax: 1-602-926-1198 support@metaice.com fax: 80-91-2386
bbs: 1-602-962-0013 islanger@metalink.de
www.metalink.de Distributors Worldwide
National U.S.A.: Santa Clara, CA www.national.com/cop8 Europe: +49 (0) 180 530 8585
1-800-272-9959 support@nsc.com fax: +49 (0) 180 530 8586
fax: 1-800-737-7018 europe.support@nsc.com Distributors Worldwide
The following companies have approved COP8 program-
mers in a variety of configurations. Contact your local office
or distributor. You can link to their web sites and get the lat-
est listing of approved programmers from National’s COP8
OTP Support page at: www.national.com/cop8.
Advantech; Advin; BP Microsystems; Data I/O; Hi-Lo Sys-
tems; ICE Technology; Lloyd Research; Logical Devices;
MQP; Needhams; Phyton; SMS; Stag Programmers; Sys-
tem General; Tribal Microsystems; Xeltek.
Customer Support
Complete product information and technical support is avail-
able from National’s customer response centers, and from
our on-line COP8 customer support sites.
COP8ACC Family
www.national.com39
Physical Dimensions inches (millimeters) unless otherwise noted
Order Number COP8ACC528N9 or COP8ACC528N8
NS Molded Package Number N28A
Order Number COP8ACC528M9 or COP8ACC528M8
NS Molded Package Number M28B
COP8ACC Family
www.national.com 40
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
Order Number COP8ACC520M9 or COP8ACC520M8
NS Molded Package Number M20B
Order Number COP8ACC728N9-XE or COP8ACC728N8-XE
NS Molded Package Number N28A
COP8ACC Family
www.national.com41
Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
Order Number COP8ACC728M9-XE or COP8ACC728M8-XE
NS Molded Package Number M28B
Order Number COP8ACC720M9-XE or COP8ACC720M8-XE
NS Molded Package Number M20B
COP8ACC Family
www.national.com 42
Notes
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and
whose failure to perform when properly used in
accordance with instructions for use provided in the
labeling, can be reasonably expected to result in a
significant injury to the user.
2. A critical component is any component of a life
support device or system whose failure to perform
can be reasonably expected to cause the failure of
the life support device or system, or to affect its
safety or effectiveness.
National Semiconductor
Corporation
Americas
Tel: 1-800-272-9959
Fax: 1-800-737-7018
Email: support@nsc.com
National Semiconductor
Europe Fax: +49 (0) 180-530 85 86
Email: europe.support@nsc.com
Deutsch Tel: +49 (0) 69 9508 6208
English Tel: +44 (0) 870 24 0 2171
Français Tel: +33 (0) 1 41 91 8790
National Semiconductor
Asia Pacific Customer
Response Group
Tel: 65-2544466
Fax: 65-2504466
Email: ap.support@nsc.com
National Semiconductor
Japan Ltd.
Tel: 81-3-5639-7560
Fax: 81-3-5639-7507
www.national.com
COP8ACC Family 8-Bit CMOS ROM Based and OTP Microcontrollers with
4k or 16k Memory and High Resolution A/D
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.
Products > Microcontrollers > 8-Bit COP8 Family > Mask ROM > COP8ACC5
Generic P/N 8ACC5
General Description
National Semiconductor Company
Design Purchasing Quality Company Jobs
Product Folder
COP8ACC5 8-Bit CMOS ROM Based Microcontrollers with 4k Memory and High Resolution A/D
Contents
lGeneral Description
lDatasheet
lPackage Availability, Models, Samples
& Pricing
Parametric Table
Code Memory 4 K
I/O Pins 16,24
MIWU Yes
Voltage Range 2.5 to 6.0V
Interrupts 10
USART Interface No
The COP8ACC Family ROM based microcontrollers are highly integrated COP8™ Feature
core devices with 4k memory and advanced features including a High-Resolution A/D.
These single-chip CMOS devices are suited for applications requiring a full featured, low
EMI controller with an A/D (only one external capacitor required). COP8ACC7 devices are
pin and software compatible (different VCC range) 16k OTP EPROM versions for pre-
production. Erasable windowed versions are available for use with a range of COP8
software and hardware development tools.
Family features include an 8-bit memory mapped architecture, 4 MHz CKI with 2.5µs
instruction cycle, 6 channel A/D with 12-bit resolution, analog capture timer, analog current
source and VCC/2 reference, one multi-function 16-bit timer/counter, MICROWIRE/PLUS
serial I/O, two power saving HALT/IDLE modes, MIWU, high current outputs, software
selectable I/O options, WATCHDOG™ timer and Clock Monitor, Low EMI 2.5V to 5.5V
operation and 20/28 pin packages.
Datasheet
Please use Adobe Acrobat to view PDF file(s).
If you have trouble printing, see Printing Problems.
Package Availability, Models, Samples & Pricing
Devices included in this datasheet are:
Device Memory
(bytes) RAM
(bytes) I/O
Pins Packages Temperature
COP8ACC5xxx9 4k ROM 128 15/23 20 SOIC, 28
DIP/SOIC 0 to +70°C
COP8ACC5xxx8 4k ROM 128 15/23 20 SOIC, 28
DIP/SOIC -40 to +85°C
COP8ACC7xxx9 16k OTP
EPROM 128 15/23 20 SOIC, 28
DIP/SOIC 0 to +70°C
COP8ACC7xxx8 16k OTP
EPROM 128 15/23 20 SOIC, 28
DIP/SOIC -40 to +85°C
Title Size
(in
Kbytes) Date View
Online Download Receive via
Email
COP8ACC Family 8-Bit CMOS ROM Based and OTP Microcontrollers with 4k or 16k
Memory and High Resolution A/D 578
Kbytes 22-Aug-
00 View
Online Download Receive via
Email
Part Number Package Status Models Samples
&
Electronic
Orders
Budgetary Pricing Std
Pack
Size
Package
Marking
Type # pins SPICE IBIS Quantity $US each
COP8ACC528D9XXX SB Cerdip 28 Preliminary N/A N/A . tube
of
N/A
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COP8ACC5
28D9XXX
COP8ACC528D9ARX SB Cerdip 28 Production N/A N/A . tube
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N/A
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COP8ACC5
28D9ARX
COP8ACC528D9CHI SB Cerdip 28 Production N/A N/A . tube
of
N/A
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COP8ACC5
28D9CHI
COP8ACC528D9FHW SB Cerdip 28 Production N/A N/A . tube
of
N/A
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COP8ACC5
28D9FHW
COP8ACC520M8CIJ SOIC WIDE 20 Production N/A N/A . tube
of
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20M8CIJ
COP8ACC520M8FHW SOIC WIDE 20 Production N/A N/A . tube
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20M8FHW
COP8ACC520M9CIJ SOIC WIDE 20 Production N/A N/A . tube
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20M9CIJ
COP8ACC520M8XXX SOIC WIDE 20 Production N/A N/A .10000+ $2.1500 tube
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20M8XXX
COP8ACC520M9XXX SOIC WIDE 20 Production N/A N/A .10000+ $2.0500 tube
of
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COP8ACC5
20M9XXX
COP8ACC528D9CJN SOIC WIDE 28 Production N/A N/A . tube
of
N/A
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COP8ACC5
28D9CJN
COP8ACC528M9ARX SOIC WIDE 28 Production N/A N/A . tube
of
N/A
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COP8ACC5
28M9ARX
COP8ACC528M9CJN SOIC WIDE 28 Production N/A N/A . tube
of
N/A
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COP8ACC5
28M9CJN
COP8ACC528M8XXX SOIC WIDE 28 Production N/A N/A .10000+ $2.4000 tube
of
26
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COP8ACC5
28M8XXX
[Information as of 29-Aug-2000]
COP8ACC528M9XXX SOIC WIDE 28 Production N/A N/A .10000+ $2.3000 tube
of
26
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COP8ACC5
28M9XXX
COP8ACC5DWF9XXX wafer Production N/A N/A . N/A -
COP8ACC528N8XXX MDIP 28 Production N/A N/A .10000+ $2.4000 tube
of
13
[logo]¢U¢Z¢3¢T¢P
COP8ACC5
28N8XXX
COP8ACC528N9XXX MDIP 28 Production N/A N/A .10000+ $2.3000 tube
of
13
[logo]¢U¢Z¢3¢T¢P
COP8ACC5
28N9XXX
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