Datasheet
ADSP-BF531/ADSP-BF532/ADSP-BF533
Rev. I | Page 15 of 64 | August 2013
more bytes until the flag is deasserted. The GPIO pin is 
chosen by the user and this information is transferred to 
the Blackfin processor via bits[10:5] of the FLAG header in 
the LDR image.
For each of the boot modes, a 10-byte header is first read from 
an external memory 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.
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 pro-
grammer 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 com-
piling 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/CPU 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 
suite to emulate the on-board processor in-circuit. This permits 
the customer to download, execute, and debug programs for the 
EZ-KIT Lite system. It also supports in-circuit programming of 
the on-board Flash device to store user-specific boot code, 
enabling standalone operation. With the full version of Cross-
Core Embedded Studio or VisualDSP++ installed (sold 
separately), engineers can develop software for supported EZ-
KITs or any custom system utilizing supported Analog Devices 
processors.
Software Add-Ins for CrossCore Embedded Studio
Analog Devices offers software add-ins which seamlessly inte-
grate with CrossCore Embedded Studio to extend its capabilities 
and reduce development time. Add-ins include board support 
packages for evaluation hardware, various middleware pack-
ages, and algorithmic modules. Documentation, help, 
configuration dialogs, and coding examples present in these 
add-ins are viewable through the CrossCore Embedded Studio 
IDE once the add-in is installed.










