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uCOS-II, SAM7 port V. 1.84 oddity.

Posted: Mon Dec 15, 2008 5:46 pm
by cfranck

I just "updated" to the latest V. 1.84 port of uCOS-II.

The application note states that in the new version, all exceptions are eventually processed in
supervisor (SVC) mode and that the stack sizes for the other exception stacks (FIQ/IRQ/Abort/etc) only need to be 16 bytes large to hold R0-R3.

However, all OS_CPU_ARM_ExceptXXXXHndlr functions except for
OS_CPU_ARM_ExceptIrqHndlr start with pushing R0-R12, LR to the stack
(STMFD SP!, {R0-R12, LR} ) without switching the processor mode.

Am I missing something here, or will this behavior cause a stack overflow if the
exception stacks are only 16 bytes large as stated in the application note?