VisualDSP++ 4.5 Loader and Utilities Manual - Analog Devices

ADSP-2126x/2136x/2137x Processor Booting
To omit an initial word of 0xa5.
When -nokernel is selected, the loader utility does not place an
initial word (A5) in the boot stream as required for SPI master
booting.
To replace the FINAL_INIT block with a USER_MESG header.
The FINAL_INIT block (which typically contains the IVT code)
should not be included in the .ldr file because the contents of the
IVT (if any) is incorporated in the boot-stream. Instead, the loader
utility appends one final bock header to terminate the loader file.
The final block header has a block tag of 0x0 (USER_MESG). The
header indicates to a subroutine processing the boot stream that
this is the end of the stream. The header contains two 32-bit data
words, instead of count and address information (unlike the other
headers). The words can be used to provide version number, error
checking, additional commands, return addresses, or a number of
other messages to the importing subroutine on the processor.
The two 32-bit values can be set on the command line as arguments
to the “-nokernel[message1, message2]” switch. The first
optional argument is msg_word1, and the second optional argument
is msg_word2, where the values are interpreted as 32-bit unsigned
numbers. If only one argument is issued, that argument is
msg_word1. It is not possible to specify msg_word2 without specifying
msg_word1.) If one or no arguments are issued at the command
line, the default values for the arguments are 0x00000000.
Listing 5-1 shows a sample format for the USER_MESG header.
Listing 5-1. Internal Booting: FINAL_INIT Block Header Format
0x00000000 /* USER_MESG tag */
0x00000000 /* msg_word1 (1st cmd-line parameter) */
0x00000000 /* msg_word2 (2nd cmd-line parameter) */
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