7 Sep
2006
7 Sep
'06
4:02 p.m.
On 9/7/06, Josef Chessor <josefcub at gmail.com> wrote:
On 9/7/06, Zane H. Healy <healyzh at
aracnet.com> wrote:
Other people have pointed out the /RESET line on the User Port; I thought
I'd just point out that the RESTORE key goes right to the /NMI line. The
normal trap handler checks the keyboard for RUN/STOP and resets BASIC
(if it can). That's why it's important to press RUN/STOP, _then_ tap
RESTORE. If you try to hit both at once, you might get the timing off
just enough that you initiate the interrupt barely before you've pressed
RUN/STOP, in which case, the NMI routine will do nothing.
In any case, commercial software routinely routed the NMI vector to
a do-nothing routine to prevent you from trapping out to BASIC. Rig
up a /RESET switch off of the User Port (look up the User Port pinout
in your C= Programmer's Reference Manual to get the correct pin).
-ethan
Is there an equivalent to CTRL-ALT-Delete on the
C64 so you don't
have to turn it on and off every time you want to run a new program?
RUN/STOP-Restore is what you're looking for, but with many programs it
doesn't work due to their hijacking of the metal from the ROM.