Hello forum,
I am doing some tests on a ARM SC300 microcontroller. In a
particular test, I need to switch to user execution from privileged
execution (in thread mode). The code looks quite straight-forward as
follows:
mrs r1, CONTROL ; copy CONTROL to r1
mov r2, #1
orr r1, r1, r2 ; r1[0] = 1
msr CONTROL, r1 ; CONTROL[0] = 1 so that we will be in user mode
isb ; flush instruction pipeline
What bothers me is that the instruction "msr CON
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