A92: Compatability with 256K-TI-92, direct keyboard-access
[Prev][Next][Index][Thread]
A92: Compatability with 256K-TI-92, direct keyboard-access
Last week I wrote something about compatability with 256K-TI-92 together
with hardware-keyboard-matrix-access. I now tested my theory at
galaga92,
and realized, that I was right. galaga92.92p had only one (and sometimes
two)
NOPs, after setting the mask. because the IO-Port wasn't addressed
slowly,
by direct addressing, but very fast by indirect-data-register addressing
(e.g.:
move.w %11110111111, (a3)), I had to increase the number of NOPs to
7!!! until it worked. Because 7 NOPs are quite a lot of mem, I tested an
alternative, instead of nop I wrote move.l (a7), (a7). I needed only 2
of
these commands, to get it working.