ADSP-BF534/ADSP-BF536/ADSP-BF537
Rev. J | Page 17 of 68 | February 2014
• Boot from serial TWI memory (EEPROM/flash) – The
Blackfin processor operates in master mode and selects the
TWI slave with the unique ID 0xA0. It submits successive
read commands to the memory device starting at 2-byte
internal address 0x0000 and begins clocking data into the
processor. The TWI memory device should comply with
Philips I
2
C Bus Specification version 2.1 and have the capa-
bility to auto-increment its internal address counter such
that the contents of the memory device can be read
sequentially.
• Boot from TWI host – The TWI host agent selects the slave
with the unique ID 0x5F. The processor replies with an
acknowledgement and the host can then download the
boot stream. The TWI host agent should comply with
Philips I
2
C Bus Specification version 2.1. An I
2
C multi-
plexer can be used to select one processor at a time when
booting multiple processors from a single TWI.
For each of the boot modes, a 10-byte header is first brought in
from an external device. The header specifies the number of
bytes to be transferred and the memory destination address.
Multiple memory blocks can be loaded by any boot sequence.
Once all blocks are loaded, program execution commences from
the start of L1 instruction SRAM.
In addition, Bit 4 of the reset configuration register can be set by
application code to bypass the normal boot sequence during a
software reset. For this case, the processor jumps directly to the
beginning of L1 instruction memory.
To augment the boot modes, a secondary software loader can be
added to provide additional booting mechanisms. This second-
ary loader could provide the capability to boot from flash,
variable baud rate, and other sources. In all boot modes except
bypass, program execution starts from on-chip L1 memory
address 0xFFA0 0000.
INSTRUCTION SET DESCRIPTION
The Blackfin processor family assembly language instruction set
employs an algebraic syntax designed for ease of coding and
readability. The instructions have been specifically tuned to pro-
vide a flexible, densely encoded instruction set that compiles to
a very small final memory size. The instruction set also provides
fully featured multifunction instructions that allow the
programmer to use many of the processor core resources in a
single instruction. Coupled with many features more often seen
on microcontrollers, this instruction set is very efficient when
compiling C and C++ source code. In addition, the architecture
supports both user (algorithm/application code) and supervisor
(O/S kernel, device drivers, debuggers, ISRs) modes of opera-
tion, allowing multiple levels of access to core processor
resources.
The assembly language, which takes advantage of the proces-
sor’s unique architecture, offers the following advantages:
• Seamlessly integrated DSP/MCU features are optimized for
both 8-bit and 16-bit operations.
• A multi-issue load/store modified-Harvard architecture,
which supports two 16-bit MAC or four 8-bit ALU + two
load/store + two pointer updates per cycle.
• All registers, I/O, and memory are mapped into a unified
4G byte memory space, providing a simplified program-
ming model.
• Microcontroller features, such as arbitrary bit and bit-field
manipulation, insertion, and extraction; integer operations
on 8-, 16-, and 32-bit data-types; and separate user and
supervisor stack pointers.
• Code density enhancements, which include intermixing of
16-bit and 32-bit instructions (no mode switching, no code
segregation). Frequently used instructions are encoded
in 16 bits.
DEVELOPMENT TOOLS
Analog Devices supports its processors with a complete line of
software and hardware development tools, including integrated
development environments (which include CrossCore
®
Embed-
ded Studio and/or VisualDSP++
®
), evaluation products,
emulators, and a wide variety of software add-ins.
Integrated Development Environments (IDEs)
For C/C++ software writing and editing, code generation, and
debug support, Analog Devices offers two IDEs.
The newest IDE, CrossCore Embedded Studio, is based on the
Eclipse
TM
framework. Supporting most Analog Devices proces-
sor families, it is the IDE of choice for future processors,
including multicore devices. CrossCore Embedded Studio
seamlessly integrates available software add-ins to support real
time operating systems, file systems, TCP/IP stacks, USB stacks,
algorithmic software modules, and evaluation hardware board
support packages. For more information visit
www.analog.com/cces.
The other Analog Devices IDE, VisualDSP++, supports proces-
sor families introduced prior to the release of CrossCore
Embedded Studio. This IDE includes the Analog Devices VDK
real time operating system and an open source TCP/IP stack.
For more information visit www.analog.com/visualdsp. Note
that VisualDSP++ will not support future Analog Devices
processors.
EZ-KIT Lite Evaluation Board
For processor evaluation, Analog Devices provides wide range
of EZ-KIT Lite
®
evaluation boards. Including the processor and
key peripherals, the evaluation board also supports on-chip
emulation capabilities and other evaluation and development
features. Also available are various EZ-Extenders
®
, which are
daughter cards delivering additional specialized functionality,
including audio and video processing. For more information
visit www.analog.com and search on “ezkit” or “ezextender”.
EZ-KIT Lite Evaluation Kits
For a cost-effective way to learn more about developing with
Analog Devices processors, Analog Devices offer a range of EZ-
KIT Lite evaluation kits. Each evaluation kit includes an EZ-KIT
Lite evaluation board, directions for downloading an evaluation
version of the available IDE(s), a USB cable, and a power supply.
The USB controller on the EZ-KIT Lite board connects to the
USB port of the user’s PC, enabling the chosen IDE evaluation