8.10.4. Debug request

Entry into debug state via a debug request is similar to a breakpoint. However, unlike a breakpoint, the last instruction will have completed execution and so must not be refetched on exit from debug state. Therefore, entry to debug state adds three addresses to the PC, and every instruction executed in debug state adds 1.

For example, suppose that the user has invoked a debug request, and decides to return to program execution straight away. The following sequence could be used:

0 E1A00000    ; MOV R0, R0
1 E1A00000    ; MOV R0, R0
0 EAFFFFFA    ; B -6

This restores the PC, and restarts the program from the next instruction.

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