Hello,
I have a piece of code that copies BITNO bit from BITVAL location to ADDR location:
MOV ACC, @@BITVAL ; load the source location
AND ACC, #(1 << BITNO) ; extract source bit
MOVL XAR0, #(ADDR) ; address of the target location
AND *, #(~(1 << BITNO)) ; clear target bit
OR *, ACC ; OR target bit with source bit
BITVAL is allways in L0 SARAM and BITNO can be between 0 for LSB and 15 for MSB. If ADDR is also in L0 SARAM everything works fine, but if ADDR is in Peripheral Frame 1 (e.g. GPBDAT) than the target bit isn't same as source bit. If I single step the code, all executes fine. I tried inserting (seven) NOPs after AND and after OR instructions, and in this case everything is OK also.
I thought that this might be caused by pipeline conflict so I checked Device Emulation Registers values. They are all at their default values, i.e. PFs are pipeline protected.
Can anyone explain this behaviour? Appreciate any help,
Josip
