I am using Port M as GPIO, the entire port is set to output.
I am currently testing the output with a bank of 8 LED's, and have found that when outputting a "1" to Bit 1 of the port, Bit 0 goes high at the same time when it should be low. The same problem happens when Bit 3 has a "1" output to it, Bit 2 goes high at the same time!
Bit 4-7 work as expected okay, follow all outputs correctly.
It is not a solder short on the board as I can turn on either Bit 0 or Bit 2 without affecting the higher bit.
MSCAN normally uses this Port, but micro is in the out of reset state which I believe is disabled. I'm hoping that I have not set up the Port correctly as opposed to some bad silicon here. Any suggestions?
STAA DDRM ;Set PortM DDR to output
LDAA #8 ; Turn on PM 3 output
PM3 and PM2 are now BOTH high!
STAA PTM ;Turn all outputs off
All outputs off normal
STAA PTM ;Turn on PM2
PM2 on only as expected