mu @MCS@51
8-BIT CONTROL-ORIENTED MICROCONTROLLERS
Commercial/Express
8031AH18051AH18051AHP
8032N+18052N-I
8751W8751H-8
8751BW8752BI-I
High Performance HMOS Process
Internal Timers/Event Counters
2-Level interrupt Priority Structure
32 1/0 Lines (Four 8-Bit Ports)
64K External Program Memory Space
Security Feature Protects EPROM Parts
Against Software Piracy
Boolean Processor
Bit-Addressable RAM
Programmable Full Duplex Serial
Channel
111 Instructions (64 Single-Cycle)
64K External Data Memory Space
Extended Temperature Range
(–40”C to +85”C)
The MCS@51 controllers are optimized for control applications. Byte-processing and numerical operations on
small data structures are facilitated by avariety of fast addressing modes for accessing the internal RAM. The
instruction set provides aconvenient menu of 8-bit arithmetic instructions, including multiply and divide instruc-
tions. Extensive on-chip support is provided for one-bit variables as aseparate data type, allowing direct bit
manipulation and testing in control and logic systems that require Boolean processing.
The 8751His an EPROMversion of the 8051AH. It has 4Kbytes of electrically programmable ROM which can
be erased with ultraviolet light. His fully compatible with the 8051AH but incorporates one additional feature: a
Program Memory Security bit that can be used to protect the EPROM against unauthorized readout. The
8751H-8 is identical to the 8751Hbut only operates up to 8MHz.
The 8051AHP is identical to the 8051AH with the exception of the Protection Feature. To incorporate this
Protection Feature, program verification has been disabled and external memory accesses have been limited
to 4K.
The 8052AH is an enhanced version of the 8051AH. It is backwards compatible with the 8051AH and is
fabricated with HMOS IItechnology. The 8052AH enhancements are listed in the table below. Also refer to this
table for the ROM, ROMless and-EPROM versions of each product.
Device Intsrnal Memory Timera/
Event Counters Interrupts
Program Data
8031AH none 128X8RAM 2x18-Bit 5
8051AH 4K X8ROM 128 X8RAM 2x16-Bit 5
6051AHP 4K X6ROM 128 X8RAM 2x16-Bit 5
8751H4K X8EPROM 128 X8RAM 2x16-Bit 5
8751H-8 4K X8EPROM 128 X6RAM 2x16-Bit 5
6751BH 4K X8EPROM 128 X8RAM 2x16-Bit 5
8032AH none 256 X6RAM 3x16-Bit 6
6052AH 8K X8ROM 256 X8RAM 3x16-Bit 6
8752BH 8K X8EPROM 256 X8RAM 3x16-Bit 6
I
IntelCorporationassumes noresponsibilityfor the use of any circuit~ otherthan circuitryembodiedinan Intel product.No other circuitpatent
licenses are implied.Informationcontained herein supersedes previouslypublishedspecificationson theaa davices from Intel.
OINTEL CORPORATION, 1994 October 1994 Order Numben 272318-002
MCS” 51 CONTROLLER
MO-M 7P2.&P2 7
-I
I
ifl 13 II II ,, ,
JK2U
Acc b
STACK
POINTER
~M‘f2#fi+-oN,TMoD,TJ
+1 L“ L-J
I<>1 I
1ml I
... ,, ,
I7’7 1. . . . .
9
PSEN
ALE
‘%
TyG g~
E
RST-+ ‘* II I
1==4
119
P0nT3
h-+ TLATCH
n
i-
,,(-1--%=2
wPI O*1 75Pm
LHvI!RS
———————————
P] O-P3 7
7
W3I
————— —.. J
x
=272318-1
Figure 1. MCSI@51 Controller Block Diagram
PROCESS INFORMATION
The 8031AH/8051AH and 8032AH/8052AH devic-
es are manufactured on P414.1, an HMOS II pro-
cess. The 8751H/8751 H-8 devices are manufac-
tured on P421.X, an HMOS-E process. The 8751BH
and 8752BH devices are manufactured on P422.
Additional process and reliability information is avail-
able in Intel’s ComponentsQuality and Reliability
Handbook, Order No, 210997.
MCS@ 51 CONTROLLER
PACKAGES
Part Prefix Package Type ‘ja Ojc
8051AH P40-Pin Plastic DIP 45°chV 16“C/W
8031AH D40-Pin CERDIP 4!5”CIW 15“CAIV
8052AH N44-Pin PLCC 46°C/W 18°CfW
8032AH
6752BH*
8751H D 40-Pin CERDIP 45”CIW 45“CIW
8751H-8
8051AHP P40-Pin Plastic DIP 45”CIW 16°CfW
D40-Pin CERDIP 45°c/w 15“cf w
8751BH P40-Pin Plastic DIP 36”CIW 12°cf w
N44-Pin PLCC 47”C1W 16”CfW
NOTE:
*8752BHis 36”/10”for D,and38”/22”for N.
All thermal impedance data is approximate for static air conditions at IW of power dissipation. Values will
change depending on operating conditions and application. See the Intel Pac/ragingHandbook (Order Number
240800) for adescription of Intel’s thermal impedance test methodology.
~“52’80320NL’ ~
L{T2
T2EX I’__”ll
PI.’ 140 Vcc
P1.1 2 39 P’,’
P1.2 3 38 PO.1
P1.3 4 37 PO.2
P1.4 5 36 PO.3
P1.5 6 35 PO.4
P1,6 7 34 PO.5
P1.7 6 33 P06
‘1
RST 9
RU2 P3.O 10
TXD P3.1 11
INTOP3.2 12
INT1 P3,3 13
TOP3 4 14
11 P3.5 15
~P3.6 16
t% P3.7 17
XTAL2 16
XTAL1 19
‘ss+!--
29
26
27
26
25
24
23
22
21
ADO
AD1
A02
A03
AD4
AD5
AD’
3PO.7A07
3EIJvpp”
ZALEIPROG”
3%FFI
3P2.7 A15
2P2.6A14
3P2.5 A13
IP2.4 A12
1P2.3 Al 1
>P2.2 AlO
3P2 1A9
XP20 A8
PI.6 ::8:;
P*,7 .:,.:
RST io;
(Rxo) P3.O :ji:
neaslvsd** .1:;
fTXD)P3.1 :ji;
(INTo)P3.2 :!;;
(INT1)P3.3 :j:;
fTo)P3.4 :>!:
8X5X
272318-2
DIP PLCC
EPROM only
“*Do not connect reserved pins.
Figure 2. MCS@51 Controller Connections
3
MCS” 51 CONTROLLER
PIN DESCRIPTIONS
Vcc: Supply voltage.
Vss: Circuit ground.
Port O:Port Ois an 8-bit open drain bidirectional 1/0
port. As an output port each pin can sink 8LS TTL
inputs.
Port Opins that have 1‘s written to them float, and in
that state can be used as high-impedance inputs.
Port Ois also the multiplexed low-order address and
data bus during accesses to external Program and
Data Memory. In this application it uses strong inter-
nal pullups when emitting 1‘s and can source and
sink 8LS TTL inputs.
Port Oalso receives the code bytes during program-
ming of the EPROM parts, and outputs the code
bytes during program verification of the ROM and
EPROM parts. External pullups are required during
program verification.
Port 1: Port 1is an 8-bit bidirectional 1/0 port with
internal pullups, The Port 1output buffers can sink/
source 4LS TTL inputs. Port 1pins that have 1‘s
written to them are pulled high by the internal pull-
UPS,and in that state can be used as inputs. As
inputs, Port 1pins that are externally pulled low will
source current (IILon the data sheet) because of the
internal pullups.
Port 1also receives the low-order address bytes
during programming of the EPROM parts and during
program verification of the ROM and EPROM parts.
In the 8032AH, 8052AH and 8752BH, Port 1pins
P1.Oand P1.1 also serve the T2 and T2EX func-
tions, respectively.
w
Port 2emits the high-order address byte during
fetches from external Program Memory and during
accesses to external Data Memory that use 16-bit
addresses (MOVX @DPTR). In this application it
uses strong internal pullups when emitting 1‘s. Dur-
ing accesses to external Data Memory that use 8-bit
addresses (MOVX @Ri),Port 2emits the contents of
the P2 Special Function Register.
Port 2also receives the high-order address bits dur-
ing programming of the EPROM parts and during
program verification of the ROM and EPROM parts.
The protection feature of the 8051AHP causes bits
P2.4 through P2.7 to be forced to O,effectively limit-
ing external Data and Code space to 4K each during
external accesses.
Port 3: Port 3is an 8-bit bidirectional l/O port with
internal pullups. The Port 3output buffers can sink/
source 4LS TTL inputs. Port 3pins that have 1‘s
written to them are pulled high by the internal pull-
UPS,and in that state can be used as inputs. As
inputs, Port 3pins that are externally pulled low will
source current (IILon the data sheet) because of the
pullups.
Port 3also serves the functions of various special
features of the MCS 51 Family, as listed below:
Port
Pin
P3,0
P3.1
P3.2
P3,3
P3.4
P3.5
P3.6
P3.7
Alternative Function
RXD (serial input port)
TXD (serial output port)
INTO(external interrupt O)
INT1 (external interrupt 1)
TO(Timer Oexternal input)
T1 (Timer 1external input)
WR (external data memory write strobe)
~(external data memory read strobe)
IPort
Pin IAlternative Function I
P1.0 T2 (Timer/Counter 2External Input)
P1.1 T2EX (Timer/Counter 2
Capture/Reload Trigger)
Port 2: Port 2is an 8-bit bidirectional l/O port with
internal pullups. The Port 2output buffers can sink/
source 4LS TTL inputs. Porl 2pins that have 1‘s
written to them are pulled high by the internal pull-
UPS,and in that state can be used as inputs. As
inputs, Port 2pins that are externally pulled low will
source current (IILon the data sheet) because of the
internal pullups.
RST: Reset input. Ahigh on this pin for two machine
cycles while the oscillator is running resets the de-
vice,
ALE/PROG: Address Latch Enable output pulse for
latching the low byte of the address during accesses
to external memory. This pin is also the program
pulse input (PROG) during programming of the
EPROM parts.
In normal operation ALE is emitted at aconstant
rate of 1/6the oscillator frequency, and may be used
for external timing or clocking purposes. Note, how-
ever, that one ALE pulse is skipped during each ac-
cess to external Data Memory.
MCS” 51 CONTROLLER
w
PSEN: Program Store Enable is the read strobe to
external Program Memory.
When the device is executing code from external
Program Memory, PSEN is activated twice each ma-
chine cycle, except that two PSEN activations are
skipped during each access to external Data Memo-
ry
~/Vpp: External Access enable ~must be
strapped to VSSin order to enable any MCS 51 de-
vice to fetch code from external Program memory
locations starting at OOOOHup to FFFFH. ~must
be strapped to VCCfor internal program execution.
Note, however, that if the Security Bit in the EPROM
devices is programmed, the device will not fetch
code from any location in external Program Memory.
This pin also receives the programming supply volt-
age (VPP)during programming of the EPROM parts.
C2 I
El
XTAL2
n
XTAL1
cl
Vss
=272318-3
Cl, C2 =30 PF +10 PFfor Crystals
ForCeramic Resonatorscontact resonatormanufacturer.
Figure 3. Oscillator Connections
XTAL1: Input to the inverting oscillator amplifier.
XTAL2: Output from the inverting oscillator amplifi-
er,
OSCILLATOR CHARACTERISTICS
XTAL1 and XTAL2 are the input and output, respec-
tively, of an inverting amplifier which can be config-
ured for use as an on-chip oscillator, as shown in
Figure 3. Either aquartz crystal or ceramic resonator
may be used. More detailed information concerning
the use of the on-chip oscillator is available in Appli-
cation Note AP-155; “Oscillators
Iers,” Order No, 230659.
I
for Microcontrol-
To drive the device from an external clock source,
XTAL1 should be grounded, while XTAL2 is driven,
as shown in Figure 4. There are no requirements on
the duty cycle of the external clock signal, since the
input to the internal clocking circuitry is through a
divide-by-two flip-flop, but minimum and maximum
high and low times specified on the data sheet must
be observed.
EXTERNAL
OSCILLATOR
SIGNAL XTAL2
XTAL1
Vss
272318-4
Figure 4. External Drive Configuration
EXPRESS Version
The Intel EXPRESSsystem offers enhancements to
the operational specifications of the MCS 51 family
of microcontrollers. These EXPRESS products are
designed to meet the needs of those applications
whose operating requirements exceed commercial
standards.
The EXPRESS program includes the commercial
standard temperature range with burn-in, and an ex-
tended temperature range with or without burn-in.
With the commercial standard temperature range,
operational characteristics are guaranteed over the
temperature range of O“C to +70”C. With the ex-
tended temperature range option, operational char-
acteristics are guaranteed over arange of –40”C to
+85”C.
The optional burn-in is dynamic, for aminimum time
of 160 hours at 125°C with VCC =5.5V *0.25V,
following guidelines in MIL-STD-883, Method 1015.
Package types and EXPRESSversions are identified
by aone- or two-letter prefix to the part number. The
prefixes are listed in Table 1.
For the extended temperature range option, this
data sheet specifies the parameters which deviate
from their commercial temperature range limits.
5
MCS” 51 CONTROLLER
ABSOLUTE MAXIMUM RATINGS*
Ambient Temperature Under Bias –40”C to +85°C
Storage Temperature .–65°C to +150°C
Voltage on EA/Vpp Pin to Vss
8751H. . . . .. . . . .. . . . . . . –0.5V to +21.5V
8751BH/6752BH –0.5V tO +13.OV
Voltage on Any Other Pinto Vss .–0.5V to +7V
Power Dissipation. . . ... 1.5W
OPERATING CONDITIONS
NOTICE:Thisisaproductiondatasheet.Itisvalidfor
the devices indicated in the revision history. The
specificationsare subjectto changewithout notice.
*WARNING:Stressing the device beyond the “Absolute
Maximum Ratings” may cause permanent damage.
These are stress ratings orr~. Operation beyond the
“Operating Conditions” is not recommended and ex-
tended exposure beyond the “Operating Conditions”
may affect device reliabili~.
Symbol Description Min Msx Units
TA Ambient Temperature Under Bias
Commercial o+70 “c
Express –40 +65 “c
Vcc SupplyVoltage 4.5 5.5 v
Fosc OscillatorFrequency 3.5 12 MHz
DC CHARACTERISTICS (OverOperating Conditions)
All parameter values apply to all devices unless otherwise indicated
Symbol Parameter Min Max Units Test Conditions
VIL Input Low Voltage (Except ~Pinof –0.5 0.8 v
6751H and 8751H-8)
VIL1 Input Low Voltage to ~Pinof o0.7 v
6751H and 8751H-8
VIH Input High Voltage (Except XTAL2, RST) 2.0 Vcc +0.5 v
VIH1 Input High Voltage to XTAL2, RST 2.5 Vcc +0.5 vXTAL1 =Vss
VIH2 Input High Voltage to ~pin 4.5 5.5V
of 6751BH and 8752BH
VoL Output Low Voltage (Ports 1,2, 3)* 0.45 vloL =1.6 mA
VoLl Output Low Voltage (Port O,ALE, PSEN)*
8751H, 8751H-8 0.60 vioL =3.2 mA
0.45 v!OL=2.4 mA
All Others 0.45 vIOL=3.2 mA
VOH Output High Voltage (Ports 1,2,3, ALE, PSEN) 2.4 vIOH=–80 PA
VOH1 Output High Voltage (Port Oin 2.4 vIOH=–400 pA
External Bus Mode)
IIL Logical OInput Current (Ports 1,2,3, and RST) –500 pA VIN =0.45V
IILI Logical OInput Current (~)
8751H and 8751H-8 –15 mA VIN =0.45V
8751BH –lo mA VIN =Vss
8752BH –lo mA VIN =Vss
0.5 mA
7
MCS” 51 CONTROLLER
DC CHARACTERISTICS (Over Operating Conditions)
All oarameter values armlv to all devices unless otherwise indicated (Continued)
~—.-...—.—. _r r.,.-.
Symbol Parameter Min Max Units Teat Conditions
11L2 Logical OInput Current (XTAL2) –3.2 mA VIN =0.45V
ILI Input Leakage Current (Porf O)
8751Hand 8751H-8 *1or) pA 0.45< VIN <VCC
All Others t10 pA 0.45< VIN <VCC
IIH Logical 1Input Current (~)
8751H and 8751H-8 500 pA VIN= 2.4V
8751BH/8752BH 1mA 4.5V <VIN <5.5V
IIH1 Input Current to RSTto Activate Reset 500 pA VIN <(Vcc 1.5V)
Icc Power Supply Current:
8031AH/8051 AH/8051AHP 125 mA All Outputs
8032AH/8052AH/8751 BH/8752BH 175 mA Disconnected;
8751H/8751 H-8 250 mA m=Vcc
Clo PinCapacitance 10 pF Test freq =1MHz
NOTES:
1. Capacitive loading on PortsOand 2may csuse spurious noise pulses to be superimposed on the VOLS of ALE/PROG
and Ports 1and 3. The noise is dueto externalbuscapacitancedischargingintothe PortOandPort2pinswhenthesepins
make1-to-Otransitionsduringbusoperations.In the worstcases(capacitiveloading>100pF),the noisepulseon the
ALE/PROGpinmayexceed0.8V.Insuchcasesit maybedesirableto qualifyALEwithaSchmittTrigger,oruseanaddress
latchwithaSchmi~TriggerSTROBEinput.
2,ALE/PROGrefersto apinonthe8751BH.ALErefersto atimingsignalthatisoutputontheALE/PROGpin.
3. Understeadystate(non-transient)conditions,loL mustbe externallylimitedasfollows:
MaximumloL perportpin: 10mA
MaximumloL per8-bitpori -Porto: 26 mA
Ports1,2,and3: 15mA
Maximumtotal toLfor all outputpins: 71 mA
If loLexceedsthetestcondition,VOLmayexceedthe relatedspecification.Pinsarenotguaranteedto sinkcurrentgreater
thanthe listedtest conditions.
8
MCS@51 CONTROLLER
EXPLANATION OF THE AC SYMBOLS
Each timing symbol has 5characters. The first char-
acter is always a‘T’ (stands for time). The other
characters, depending on their positions, stand for
the name of asignal or the logical status of that
signal. The following is alist of all the characters and
what they stand for.
A: Address
C: Clock
D: Input Data
H: Logic level HIGH
1:Instruction (program memory contents)
L: ~level LOW, or ALE
P: PSEN
Q: Output data
R: ~signal
T: Time
V: Valid
W: WR signal
X: No longer avalid logic level
Z: Float
For example,
TAVLL =Time from Address Valid to ALE Low.
TLLPL =Time from ALE Low to PSEN Low.
AC CHARACTERISTICS (Under Operating Conditions; Load Capacitance for Port O,ALE/PROG, and
PSEN =100 pF; Load Capacitance for All Other Outputs =80 pF)
EXTERNAL PROGRAM MEMORY CHARACTERISTICS
Symbol Parameter 12 MHz Oscillator Variable Oscillator Units
Min Max Min Max
1/TCLCL Oscillator Frequency 3.5 12.0 MHz
TLHLL ALE PulseWidth 127 2TCLCL–40 ns
TAVLL Address Valid to ALE Low 43 TCLCL–40 ns
TLLAX Address Hold after ALE Low 48 TCLCL–35 ns
TLLIV ALE Low to Valid Instr In
8751H183 4TCLCL– 150 ns
All Others 233 4TCLCL– 100 ns
TLLPL ALE LOW to PSENLOW 58 TCLCL–25 ns
TPLPH PSEN PulseWidth
8751H190 3TCLCL–60 ns
All Others 215 3TCLCL–35 ns
TPLIV PSENLow to Valid Instr In
8751H 100 3TCLCL– 150 ns
All Others 125 3TCLCL– 125 ns
TPXIX Input Instr Hold after PSEN o 0 ns
TPXIZ Input Instr Float after PSEN 63 TCLCL–20 ns
TPXAV PSENto Address Valid 75 TCLCL–8 ns
TAVIV Address to Valid Instr In
8751H287 5TCLCL–1 50 ns
All Others 302 5TCLCL–1 15 ns
TPLAZ PSEN Low to Address Float 20 20 ns
TRLRH ~PulseWidth 400 6TCLCL– 100 ns
TWLWH WR Pulse Width 400 6TCLCL– 100 ns
TRLDV ~Low to Valid Data In 252 5TCLCL– 165 ns
TRHDX Data Hold after ~o 0 ns
TRHDZ Data Float after ~97 2TCLCL–70 ns
TLLDV ALE Low to Valid Data In 517 8TCLCL–1 50 ns
-.. .. . . . , , . ,–,. , -—.—,.– .,. -nl-n, n, .ec --
IAVUV IAaaress 10valla Ua[a mIIDUD I I YI~LUL— 103 Irm
9
MCS@51 CONTROLLER
EXTERNAL PROGRAM MEMORY CHARACTERISTICS (Continued)
Symbol
TLLWL
TAVWL
TQVWX
TQVWH
TWHQX
TRLAZ
TWHLH
‘arame’erI---%#
ALE Low to RDor WR Low 200
Address to ~or WR Low 203
Data Valid to WR Transition
8751HI13
All Others 23
Data Valid to WR High 433
Data Hold after WR 33
RD Low to Address Float
RDor WR High to ALE High
8751H 33
All Others 43
cillator VariableOscillator Units
Max Min Max
300 3TCLCL–50 3TCLCL+ 50 ns
4TCLCL– 130 ns
TCLCL–70 ns
TCLCL–60 ns
7TCLCL– 150 ns
TCLCL–50 ns
20 I I 20 I ns I
133 TCLCL–50 TCLCL+ 50 ns
123 TCLCL–40 TCLCL+40 ns
NOTE:
“The 8751H-8 is identicalto the 8751Hbut onlyo~eratesutI to 8MHz.Whencalculatingthe AC Characteristicsfor the
8751 H-8, use the 8751 Hformula for variable oscillators.
10
MCS@51 CONTROLLER
EXTERNAL PROGRAM MEMORY READ CYCLE
w--- TLHLL_
ALE \ , /\
TLLPL-~TPLPH
-TAVLL+ +TLLIV
PSEN /
TLLAX
PORTO
1
PORT2xAO
-A15 xA8 -A15
272318-5
EXTERNAL DATA MEMORY READ CYCLE
ALE Y\/
+TLHLL+ TWHLH
PSEN
‘LLOv ~
TLLWL TRLRH –—
m+TAVLL +bi
_TLLAX —TRLDV4 TRHOX+
PORTO AO-A7 FROMRI OR OPL OATAIN
.
.TAVOV b
PORT2xrP2.O-P2.7 OR A8-A15 FROMDPH xA8-A15 FROMPCH
272318-6
EXTERNAL DATA MEMORY WRITE CYCLE
ALE \ , \/
TLHLL— TWHLH
m/
‘TLLwL~TwLwH *
WT 1TAVLL k1
+TLLAX 7t=-
TQVWX
:rTWHQX
TQVWH
II I1
PORTO AO-A7
FROMRIOR OPL MOATAOUT xxAO-A7 FROMFCL
I
PORT2 xP2.O-P2.7 OR A8-A15 FROMOPH xA8-A15 FROMPCH
272318-7
11
M=” 51 CONTROLLER
SERIAL PORT TIMING—SHIFT
Test Conditions: Over ODeratina Conditions: Load Capacitance =80 rJF
Symbol
TXLXL
TQVXH
TXHQX
TXHDX
TXHDV
Parameter 12 MHz Oscillator VariableOscillator Unite
Min Max Min Max
Serial Port Clock Cycle Time 1.0 12TCLCL ps
Output Data Setup to Clock Rising 700 1OTCLCL– 133 ns
Edge
Output Data Hold after Clock 50 2TCLCL–1 17 ns
Rising Edge
Input Data Hold after Clock Rising o0ns
Edge
Clock Rising Edge to Input Data 700 10TCLCL– 133 ns
Valid
;HI17REGISTERMODETIMINGWAVEFORMS
INSTRUCTION IOI1I2I3I4I5I6I7I8I
ALE n n nnnnnnnnnnnnnnnnI
I-TXLXL-7
CLOCK
WI-TXHQX I
OUTPUTOATA o1)( 1 2 x3x4x5x6x7/
,+
SET TI
INPUT DATA
~4
SET RI
272318-8
12
MCS@51 CONTROLLER
EXTERNAL CLOCK DRIVE
Symbol Parameter Min Max Units 1
1/TCLCL Oscillator Frequency (except 8751H-8) 3.5 12 MHz
8751H-8 3.5 8MHz
TCHCX High Time 20 ns
TCLCX Low Time 20 ns
ITCLCH IRise Time II20 Ins I
TCHCL Fall Time 20 ns
EXTERNAL CLOCK DRIVE WAVEFORM
TCHCX TCLCH _~TCliCL
2.5 tat2.5 A
-— TCLCX
+TCLCL w
272318-9
AC TESTING INPUT, OUTPUT WAVEFORM
2.4 2.0 2.0
>< TEST POINTS
0.s 0.8
0.45
272318-10
AC Testing: Inputsare driven at 2.4V for aLogic“1” and 0.45V
for aLogic “O”. Timing measurements ara made at 2.OV for a
Logic“1” and 0.8V for aLogic“O”.
MCS@51 CONTROLLER
EPROM CHARACTERISTICS
Table3.EPROMProgrammingModea
Mode RST PSEN ALE mP2.7 P2.6 P2.5 P2.4
Program 1 0 o* VPP 10xx
Verify 1 0 1 1 0 0 xx
Security Set 1 0 o* VPP 11xx
NOTE:
“1” =logichighforthat pin
“O” =logiclowfor thatpin
“X” =“don’t care”
PROGRAMMING THE 8751H
To be programmed, the part must be running with a
4to 6MHz oscillator. (The reason the oscillator
needs to be running is that the internal bus is being
used to transfer address and program data to appro-
priate internal registers.) The address of an EPROM
location to be programmed is applied to Port 1 and
pins P2.O-P2.3 of Port 2, while the code byte to be
programmed into that location is applied to Port O.
The other Porl 2pins, and RST, PSEN,and ~/Vpp
should be held at the “Program” levels indicated in
Table 3. ALE/PROG is pulsed low for 50 ms to pro-
gram the code byte into the addressed EPROM lo-
cation. The setup is shown in Figure 5.
Normally ~~is held at alogic highflntil just
before ALE/PROG is to be pulsed. Then EA/Vpp is
raised to +21 V, ALE/PROG is pulsed, and then
~/Vpp is returned to alogic high. Waveforms and
detailed timing specifications are shown in later sec-
tions of this data sheet.
+5V
a
Vcc
AOOR A&b? p?
—FFH wPGM DATA
P2.0–
U–All P2.3 8751H
‘=’’-”TCAREJ=E‘LEl=$=-
U
Vlli P2.7
XTAU 5F&vPP
4-SUN* n
XTAL1 RST VIH1
Vss PSEN
..
27231a-1 I
Figure5.ProgrammingConfiguration
“VPP” =+21V *0.5V
*ALEis pulsedlowfor 50ms
Note that the ~/VPP pin must not be allowed to go
above the maximum specified VPP level of 21.5Vfor
any amount of time. Even anarrow glitch above that
voltage Ievei can cause permanent damage to the
device. The VPP source should be well regulated
and free of glitches.
Program Verification
If the Security Bit has not been programmed, the on-
chip Program Memory can be read out for verifica-
tion purposes, if desired, either during or after the
programming operation. The address of the Program
Memory location to be read is appiied to Port 1 and
pins P2.O-P2.3. The other pins should be held at the
“Verify” Ieveis indicated in Tabie 3. The contents of
the addressed location will come out on Port O.Ex-
ternal pullups are required on Port Ofor this opera-
tion.
The setup, which is shown in Figure 6, is the same
as for programming the EPROM except that pin P2.7
is held at alogic low, or may be used as an active-
Iow read strobe
+5V
?
Vcc
mu
w+DATA
—FFH (USE 10K
PULLUPS]
W51H
x
~. ,,W,, CARE,. -~~b
X-9 P2.5 ALE
VIL dP2.S VIH
ENAS4E .P2 7G
J- XTAU
4-6 MHZmRST hVIH1
XTAL1
Vss PSEN
.
27231S-12
Figure6.ProgramVerification
14
MCS@51 CONTROLLER
EPROM Security
The security feature consists of a‘locking” bit which
when programmed denies electrical access by any
external means to the on-chip Program Memory.
The bit is programmed as shown in Figure 7. The
setup and procedure are the same as for normal
EPROM programming, except that P2.6 is held at a
logic high, Porl O,Port 1 and pins P2.O–P2.3may be
in any state. The other pins should be held at the
“Security” levels indicated in Table 3.
Once the Security Bit has been programmed, it can
be cleared only by full erasure of the Program Mem-
ory. While it is programmed, the internal Program
Memory can not be read out, the device can not be
further programmed, and it cannotexecuteoutof
externalprogrammemory.Erasing the EPROM,
thus clearing the Security Bit, restores the device’s
full functionality. It can then be reprogrammed.
+5V
X=OGN’T CARE” o
f
Vcc
{: ‘-
PI
mx
P2.0-
XP2.3 8751H
P2.4 ALE ALE/PROO
P2.5 50 ma PULSE TO GND
P2.6
VIM P2,7 fi +EAYPP
XTAU
mRST WH1
XTAL1
Vss PSEN 7
**272318-13
Erasure Characteristics
Erasure of the EPROM begins to occur when the
device is exposed to light with wavelengths shorter
than approximately 4,000 Angstroms. Since sunlight
and fluorescent lighting have wavelengths in this
range, exposure to these light sources over an ex-
tended time (about 1week in sunlight, or 3years in
room-level fluorescent lighting) could cause inadver-
tent erasure. If an application subjects the device to
this type of exposure, it is suggested that an opaque
label be placed over the window.
Figure7.ProgrammingtheSecurityBit
The recommended erasure procedure is exposure
to ultraviolet light (at 2537 Angstroms) to an integrat-
ed dose of at least 15 W-sec/cm2. Exposing the
EPROM to an ultraviolet lamp of 12,000 pW/cm2
rating for 20 to 30 minutes, at adistance of about
1inch, should be sufficient.
Erasure leaves the array in an all 1‘s state.
EPROM PROGRAMMING AND VERIFICATION CHARACTERISTICS
TA =21°C to 27”C; VCC =5V +10%; VSS =OV
Symbol Parameter Min Max Unita
VPP Programming Supply Voltage 20.5 21.5 v
IPP Programming Supply Current 30 mA
1/TCLCL Oscillator Frequency 4 6 MHz
TAVGL Address Setup to PROGLow 46TCLCL
TGHAX Address Hold after PROG 48TCLCL
TDVGL Data Setup to PROG Low 48TCLCL
TGHDX Data Hold after~ 48TCLCL
TEHSH P2.7 (ENABLE) High to VPP 48TCLCL
TSHGL VPPSetup to PROGLow 10 ps
TGHSL VPP Hold after PROG 10 ps
TGLGH PROGWidth 45 55 ms
TAVQV Address to Data Valid 48TCLCL
TELQV ENABLE Low to Data Valid 48TCLCL
TEHQZ Data Float after ENABLE o48TCLCL
15
MCS” 51 CONTROLLER
GI-” ”nl r“”” ”mrnmrlmn. wI-8. ,Lrl.. .“4-s .m“.. ..-. b. “..8.,”
PROGRAMMING VERIFICATION
P1.O-PI.7
P3,0-P3,3 (ADDRESS
$ J
PORTO{,DATAIN
TOVGL —TGHOX
TAVGL TGHAX
kLE/PROG
\~
TSHGL TGHSL
TGLGH
21V *.5V
r
\
mHIGH
Fi.vPP TTLHIGH TTLHIGH
TSHSN
TELOV
P3.7
(ENABLE) 1\
272318-14
For programmingconditionssee Figure5. For verificationconditionssee Figure6.
16
inlA MCS” 51 CONTROLLER
Programming the 8751BH/8752BH
To be programmed, the 875XBH must be running
with a4to 6MHz oscillator. (The reason the oscilla-
tor needs to be running is that the internal bus is
being used to transfer address and program data to
appropriate internal registers.) The address of an
EPROM location to be programmed is applied to
Porl 1 and pins P2.O-P2.4 of Port 2, while the code
byte to be programmed into that location is applied
to Port O. The other Port 2 and 3 pins, and RST,
PSEN,and ~/Vpp should be held at the “Program”
levels indicated in Table 1.ALE/PROG is pulsed low
to croaram the code bvte into the addressed
Normally ~&is held at alogic high until just
before ALE/PROG is to be pulsed. Then ~/Vpp is
raised to Vpp, ALE/PROG is pulsed low, and then
~/Vpp is returned to avalid high voltage. The volt-
age on the ~/Vpp pin must be at the valid EA/Vpp
high level before averify is attempted. Waveforms
and detailed timing specifications are shown in later
sections of this data sheet.
Note that the ~/Vpp pin must not be allowed to go
above the maximum specified Vpp level for any
amount of time. Even anarrow glitch above that volt-
age level can cause permanent damage to the de-
vice. The Vpp source should be well regulated and
EPROfl location. The setu’pis shown in Figure 8. free of glitches.
+5V
Vcc
Po
1~RST E/vpp ~+12.75V
ALE/PROG ~25 100 p, PULSESTOGND
1~P3.6
875X,, ~~“
1~P3.7 P2.7 ~1
lJ- XTAL2P2.6 ~o
4-6 MHz
T= ;XTAL1P2.O
-P2,4
‘ks
=272318-15
—.
Figure8.Programmingthe EPROM
Table4.EPROMProgrammingModeafor875XBH
MODE RST ALE/
PSEN ml
PROG Vpp P2.7 P2.6 P3.6 P3.7
Program Code Data 10o* Vpp 1 0 1 1
Verify Code Data 1 0 11 0 0 1 1
Program Encryption Tabie 10o* Vpp 1 0 01
Use Addresses O-1FH
Program Lock ~= 11 0 o* Vpp 1111
Bits (LBx) x=2 1 0 o* Vpp 110 0
Read Signature 1011000 0
NOTES:
“1” =Validhighforthatpin
“O” =Validlowfor thatpin
“vpp” = + 12.75V+0.25V
*ALE/PROGispulsedlowfor 100USfor programming.(Quick-PulseProgramming)
17
MCS@51 CONTROLLER
QUICK-PULSE PROGRAMMING
ALGORITHM
The 875XBH can be programmed using the Quick-
Pulse Programming Algorithm for microcontrollers.
The features of the new programming method are a
lower Vpp (12.75 volts as compared to 21 volts) and
ashorter programming pulse. For example, it is pos-
sible to program the entire 8Kbytes of 875XBH
EPROM memory in less than 25 seconds with this
algorithm!
To program the part using the new~rithm, Vpp
must be 12,75 f0.25 Volts. ALE/PROG is pulsed
low for 100 pseconds, 25 times as shown in
Figure 9, Then, the byte just programmed may be
verified. After programming, the entire array should
be verified. The Program Lock features are pro-
grammed using the same method, but with the setup
as shown in Table 4. The only difference in program-
ming Lock features is that the Lock features cannot
be directly verified. Instead, verification of program-
ming is by observing that their features are enabled.
PROGRAM VERIFICATION
If the Lock Bits have not been programmed, the on-
chip Program Memory can be read out for verifica-
tion purposes, if desired, either during or after the
programming operation. The address of the Program
Memory location to be read is applied to Port 1 and
pins P2.O-P2.4. The other pins should be held at
the “Verify” levels indicated in Table 1. The con-
tents of the addressed location will come out on Port
O. External pullups are required on Port Ofor this
operation. (If the Encryption Array in the EPROM
has been programmed, the data present at Port O
will be Code Data XNOR Encryption Data. The user
must know the Encryption Array contents to manual-
ly “unencrypt” the data during verify.)
The setup, which is shown in Figure 10, is the same
as for programming the EPROMexcept that pin P2.7
is held at alogic low, or may be used as an active
low read strob~.
,~25p”LsEs ~
ALEM
n--------
I
10 P,MIN 100JM
*lops
ALE/PROG:
01272318-16
Figure9.PROGWaveforma
+~v
‘rh10kJl
AO-A7 P!
RST
P3.6
1P3.7
LXTAL2
4-6 MHz
XTAL1
Vss
=
Vcc
-F’
X8
Po PGM
DATA
rmpp
ALE/PRW 1
B75xBH =0
P2.7 0(i-mm
P2.6 0
P2.O
-P2.4
F
A8-A12
272318-17
Figure10.VerifyingtheEPROM
18
PROGRAM MEMORY LOCK
The two-level Program Lock system consists of 2
Lock bits and a 32-byte Encryption Array which are
used to protect the program memory against soft-
ware piracy.
ENCRYPTION ARRAY
Within the EPROM array are 32 bytes of Encryption
Array that are initially unprogrammed (all 1s). Every
time that abyte is addressed during averify, 5ad-
dress lines are used to select abyte of the Encryp-
tion Array. This byte is then exclusive-NORed
(XNOR) with the code byte, creating an Encrypted
Verify byte. The algorithm, with the array in the un-
programmed state (all 1s), will return the code in its
original, unmodified form.
It is recommended that whenever the Encryption Ar-
ray is used, at least one of the Lock Bits be pro-
grammed as well.
LOCK BITS
Also included in the EPROM Program Lock scheme
are two Lock Bits which function as shown in Table
5.
Erasing the EPROM also erases the Encryption Ar-
ray and the Lock Bits, returning the part to full un-
locked functionality.
MCS@51 CONTROLLER
Table5.LockBitsandtheirFeatures
LogicEnabled
LB1
u
=
Minimum Program Lock features
enabled. (Code Verify WIIIstill be
PuMOVC instructions executed from
external program memory are
disabled from fetching code bytes
from internal memory, EA is
sampled and latched on reset,
and further programming of the
EPROMis disabled
PIPSame as above, but Verify is also
disabled
UIPIReservedfor Future Definition I
=Programmed
=Unprogrammed
READING THE SIGNATURE BYTES
The signature bytes are read by the same procedure
as anormal verification of locations 030H and 031H,
except that P3.6 and P3.7 need to be pulled to a
logic low. The values returned are:
(030H) =89H indicates manufactured by Intel
(031H) =51H indicates 8751BH
52H indicates 8752BH
To ensure proper functionality of the chip, the inter-
nally latched value of the ~pin must agree with its
external state.
19
MCS” 51 CONTROLLER
ERASURE CHARACTERISTICS
Erasure of the EPROM begins to occur when the
8752BH is exposed to light with wavelengths shorter
than approximately 4,000 Angstroms. Since sunlight
and fluorescent lighting have wavelengths in this
range, exposure to these light sources over an ex-
tended time (about 1week in sunlight, or 3years in
room-level fluorescent lighting) could cause inadver-
tent erasure. If an application subjects the device to
this type of exposure, it is suggested that an opaque
label be placed over the window.
The recommended erasure procedure is exposure
to ultraviolet light (at 2537 Angstroms) to an integrat-
ed dose of at lease 15 W-see/cm. Exposing the
EPROMto an ultraviolet lamp of 12,000 pW/cm rat-
ing for 30 minutes, at adistance of about 1inch,
should be sufficient.
Erasure leaves the array in an all Is state.
EPROM PROGRAMMING AND VERIFICATION CHARACTERISTICS
(T,4 =21°C to 27”C, Vcc =5.OV +10%, Vss =OV)
Symbol Parameter Min Max Units
Vpp Programming Supply Voltage 12.5 13.0 v
Ipp Programming Supply Current 50 mA
1/TCLCL Oscillator Frequency 48MHz
TAVGL Address Setup to PROG Low 48TCLCL
TGHAX Address Hold After PROG 48TCLCL
TDVGL Data Setup to PROGLow 48TCLCL
TGHDX Data Hold After PROG 48TCLCL
TEHSH P2.7 (ENABLE) High to Vpp 48TCLCL
TSHGL Vpp Setup to PROGLow 10 ps
TGHSL Vpp Hold After PROG 10 ps
TGLGH PROGWidth 90 110 ps
TAVQV Address to Data Valid 48TCLCL
TELQV ENABLE Low to Data Valid 48TCLCL
TEHQZ Data Float After ENABLE o48TCLCL
TGHGL PROGHigh to PROGLow 10 ps
EPROM PROGRAMMING AND VERIFICATION WAVEFORMS
PROGRAMMING VERIFICATION
‘::=&z ~.-~}
ADDRESS ADDRFSS
TAvQV
DATAIN DATAOUT
TDVGL TGHDX
TAVGL Pu& TGHAX
TSHGL dTGHsL
TGLGH TGHGL
~wpp t[A/HIGH
TELQV LTEHQZ
P2.7
272318-18
20
MCS@51 CONTROLLER
DATA SHEET REVISION HISTORY
Datasheets are changed as new device information becomes available. Verify with your local Intel sales office
that you have the latest version before finalizing adesign or ordering devices.
The following differences exist between this datasheet (272318-002) and the previous version (272318-001):
1. Removed QP and QD (commercial with extended burn-in) from Table 1. EXPRESS Prefix Identification.
This datasheet (272318-001) replaces the following datasheets:
MCS@51 Controllers (270048-007)
8051AHP (270279-004)
8751BH (270248-005)
8751BH EXPRESS (270708-001)
8752BH (270429-004)
8752BH EXPRESS (270650-002)
21