I have implemented a second stage bootloader and want to use a shared variable in L1 RAM. This variable will be shared with the main application.
Therefore I created a section in both ldf-files with NO_INIT
and I define the variable
#pragma section ("SHARED_UPDATEVAR", NO_INIT)
volatile unsigned char Update_Req;
My software in the main application write to the variable Update_Req and performs an software reset through watchdog like in https://ez.analog.com/dsp/blackfin-processors/bf70x/f/q-a/12908/how-to-enable-h-w-reset-when-watch-dog-timer-expired.
Always when my second stage bootloader starts after the watchdog reset and want to read the variable Update_Req in L1 RAM the variable is zero.
So my question is what is the status of L1 SRAM after a watchdog reset? Does it retain the data it held before the reset or is it indeterminate?
I implemented the same in the BF534 an it works but not with my BF707.