Analog Devices VISUALDSP++ 3.5, Manual, Page: 67 / 166

Vi+ Loader Manual 2-37
for 16-Bit Processors
Blackfin Processor Loader/Splitter
ADSP-BF531/BF532/BF533 and ADSP-BF561 Multiple
.DXE Booting
This section describes how to boot more than one
.DXE
file into a
ADSP-BF531/BF532/BF533 and ADSP-BF561 processor. The informa-
tion presented in this section applies to all of the named processors. For
additional information on the ADSP-BF561 processor, refer to
“ADSP-BF561 Multiple .DXE Booting” on page 2-36 .
The ADSP-BF531/BF532/BF533 and ADSP-BF561 loader file structure
and the silicon revision of 0.1 and higher allow to boot multiple
.DXE
files
into a single processor from external memory. Each executable file is pre-
ceded by a 4-byte count header, which is the number of bytes within the
executable, including headers. This information can be used to boot a spe-
cific
.DXE
into the processor. The 4-byte
.DXE
count block is encapsulated
within a 10-byte header to be compatible with the silicon revision 0.0. For
more information, see “Blocks and Block Headers” on page 2-19.
Booting multiple executables can be accomplished by one of the following
methods.
1. Use the second-stage loader switch, “-l userkernel” . This option
allows to use your own second-stage loader or kernel.
After the second-stage loader gets booted into internal memory via
the on-chip boot ROM, it has full control over the boot process.
Now the second-stage loader can use the
.DXE
byte counts to boot
in one or more
.DXE
s from external memory.