ARM Cortex R4F Instrukcja Użytkownika Pobierz pdf (Strona 41)

Exception Handlers and Return

An exception handler (ISR) is a software routine that is executed

when a specific exception condition occurs.

Most, but not all, exception handlers return to the previous code.

Interrupt Stacking

Old SP

PSR

Return Address

R12

Increasing Addresses

Eights words

pushed onto

stack by

exception

response.

Exception return occurs when in Handler

Mode and one of the following

instructions is executed:

• POP/LDM includes the PC, or

• LDR with PC as the destination, or

• BX with any register as the source

1 2 ... 36 37 38 39 40 41 42 43 44 45 46 ... 63 64

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ARM Cortex R4F Instrukcja Użytkownika Strona 41