Analog Devices VISUALDSP++ 3.5, Manual

Page: 49 / 166

Vi+ Loader Manual 2-19
for 16-Bit Processors
Blackfin Processor Loader/Splitter
ADSP-BF531/BF532/BF533 Processor Boot Streams
The following sections describe the boot stream, header, and flag frame-
work for ADSP-BF531, ADSP-BF532, and ADSP-BF533 processors.
• “Blocks and Block Headers” on page 2-19
• “Flags of Block Header” on page 2-20
• “Initialization Blocks” on page 2-21
The ADSP-BF531/BF532/BF533 processor boot stream is similar to the
boot stream that uses a second-stage kernel of ADSP-BF535 processors
(detailed in
“ADSP-BF535 Processor Boot Streams” on page 2-8 ). How-
ever, since the former processors do not employ a kernel, their boot
streams do not include the kernel code and the associated 4-byte header
on the top of the kernel code. There is also no 4-byte global header.
Blocks and Block Headers
As the loader converts the code from an input
.DXE
file into blocks com-
prising the output loader file, each block is getting preceded by a 10-byte
header (
Figure 2-10 ), followed by a block body (if it is a non-zero block)
or no block body (if it is a zero block). A description of the header struc-
ture can be found in
Table 2-3 .
Table 2-3. ADSP-BF531/BF532/BF533 Block Header Structure
Bit Field Description
Address 4-byte address at which the block resides in memory.
Count 4-byte number of bytes to boot.
Flag 2-byte flag containing information about the block “Flags of Block
Header” on page 2-20 describes the flag structure.