RUN STOP / RESTORE problem

Post by **Jeff-20** » Sat Apr 24, 2004 12:44 pm

I have had this problem for the past ten years on various VIC 20s. Every time I exit a running program with the RUN STOP/ RESTORE key combo I run a 70% chance of the computer crashing!

I am not exaggerating. I always save to disk before running for this reason. A good 70% of the interruptions of a running program result in a ready screen; however, the system is unresponsive.

Actually, most of the time, I'll type something and get a ?SYNTAX ERROR and the cursor will be displaced just to the left of center at the bottom of the screen. Then the computer is completely unresponsive. I must reboot, reload my program and continue from there.

Has anyone else had this problem? I have had it on several VICs. What could be the cause and/or solution?

aneurysm · Post by **aneurysm** » Sun Apr 25, 2004 1:40 am

that's just screwy
replace the fuce
sorry
i;m drunk
and that's no help

Leeeeee · Post by **Leeeeee** » Sun Apr 25, 2004 2:42 am

This is a known problem with Vics and is caused by poor contact on the RESTORE key causing so many NMI interrupts that the stack overflows.

The obvious solution is to replace the key with one that has better contacts, or at least cleaning and lubricating (with contact lube) the one you have.

Another possible solution is to connect a small (470pF or so) capacitor across the switch to 'filter' the contact bounce.

Lee.

Post by **Jeff-20** » Sun Apr 25, 2004 11:52 am

so if I press it hard and fast will I be less likely to have this problem?

Leeeeee · Post by **Leeeeee** » Fri Apr 30, 2004 12:26 am

It depends on how trashed the switch is but mostly yes.

Trouble is doing that will eventually break it.

Lee.