14.8.6. Reading a current mode ARM register
in the range r0-r14
Use the following sequence to read a current mode ARM register
in the range r0-r14:
SCAN_N 5 ; select DTR
ITRSEL ; select the ITR and EXTEST
INST MCR p14,0,Rd,c0,c5,0 ; instruction to copy Rd into CP14 debug
; register c5
RTI
INTEST ; select the DTR and INTEST
LOOP
DATA 0x00000000 Ready readData
UNTIL Ready==1 ; wait until the instruction ends
Save value in readData
Note
Register r15 cannot be read in this way because the effect
of the required MCR is to take an Undefined exception.
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