marshallmallow wrote on Monday, June 15, 2009:
I’ve written a boot loader for an ARM7 lpc2148. The bootloader simply looks for a firmware file on an sd card and writes the file out to program memory. It then starts execution of the firmware. The firmware is the same as the orginal app, only the linker script designates program memory starting at address 0x20000.
When the bootloader starts execution of the app, I’m seeing some very odd behavior. When the first task is run, if I step into each line of code, everything works fine. If I step over each line of code, then the first time I step over a function in the task, execution goes back to the bootloader. I’m not seeing any kind of ARM exception such as data abort, execution just appears to restart at 0x0000.
Is there something I’m missing? I don’t see why there would be any problem with what I’m doing. Since all of the stacks are reinitialized when the app starts execution and the first task is actually starting, then why would there be a problem during the first function call?
Thanks for any insight.