Hiya, WIllard,
> *The* Mike Nugent? <waynesworld>We're not worthy!!!</waynesworld> :-)
LOL I think it’s the other way around these days.
> Humm, higher address, sets both bits? Interesting, I'll have to
> experiment further.
I took another look, and it appears the address Tandy gave you is where it
checks to see whether CTRL-C or CTRL-S is pressed, setting the carry flag if
so. Here’s what this area of ROM looks like in my notes:
———
KEYX
7270H - Check keyboard queue for pending characters
Exit:
A - Destroyed
Z flag - Set if character pending
C flag - Set if break is present
Note: called via CHSNS
CTLCHK
7283H - Check for break (Control C) or wait (Control S)
Exit:
A - Destroyed
C flag - Set if Control C or S
Z flag - Set if no control C or S
Note: called from KEYX (7270)
BRKCHK
729FH - Check to see if SHIFT BREAK is being pressed.
Exit:
A - Destroyed
Z flag - Set if shift break is being pressed
C flag - Set if shift break is being pressed
72B1H - Scan BREAK, CAPS, NUM, CODE, GRAPH, CONTROL, and SHIFT key column of
keyboard. Reset the bit in the A register that corresponds the key
being pressed
Exit:
A - Each reset bit corresponds to a key being pressed
(BREAK=bit 7, CAPS=bit 5, etc.)
———
I think I’ll have to post this version of the maps somewhere soon. Just have to
deal with some urgent business first. Meantime, hoping the above is helpful.
I’m also going to send a copy (about 93Kb) to your sdc.org address if you say
it’s okay.
— Nuge —
On Apr 5, 2017, at 3:18 PM, Willard Goosey <[email protected]> wrote:
> On Mon, 3 Apr 2017 12:23:05 -0400
> Mike Nugent <[email protected]> wrote:
>
> *The* Mike Nugent? <waynesworld>We're not worthy!!!</waynesworld> :-)
>
>> A file I have, named ‘M100 RAM/ROM maps’ shows this:
>>
>> BRKCHK
>> 729FH - Check to see if SHIFT BREAK is being pressed.
>> Exit:
>> A - Destroyed
>> Z flag - Set if shift break is being pressed
>> C flag - Set if shift break is being pressed
>
>
> Humm, higher address, sets both bits? Interesting, I'll have to
> experiment further.
>
> More complications... :-(
>
> Willard
