[Coco] PIA keyboard input?

[Robert Gault]

James Dessart wrote:
> 
> On 7-Dec-03, at 3:23 PM, peak wrote:
> 
>> Since "POLCAT's" scan routine already does this why do you
>> want to do it directly?
> 
> 
> I'm trying to bypass the BASIC ROMs entirely, writing my own IO routines 
> and such.
> 
> It seems I actually need to do a ROL on the address directly, as simply 
> outputting the desired sequence gives me nothing.  So if I output 
> "10111111" to the column address, I get all 1's from row address.  Is 
> there some other way to do it than ROLing the column address with a 0?
> 
> James
> 
> 
Whether you ROL/ROR or ST depends on whether you want to detect one 
specific key or any possible key press combination. Clearly if you want 
any key you must test all possible column/row combinations.