Correct way to I/O

[dcclark]

I wish to preserve the state of all but pins 0 - 2 of port J and then write a variable to those pins. I did the following:

[Guest]

You should mask out the higher bits from buffer[2] to prevent corruption:

[dcclark]

Thanks Mr. Guest. That is one of those "Why didn't I think of that?"

[asmboy]

output_J( ( input_j()&F8) | ( buffer[2]&7));

[dcclark]

[dcclark]

And of course my CCS PCWHD compiler complained. The code should be thusly: output_j((input_j() & 0xF8) | (buffer[2] & 0x7));
Thanks again.