Denial

At the end, it was CPU that failed, but probably the first time i have changed CPU, i didn't change old, one sided, socket under CPU yet, so it gave me the same error. After a long time, socketing all the chips, and not finding the problem, i started again to exchange chips from working VC20! After ...

Given that you have a screen of the right size and colour a steady character definition that looks right I would say that both the KERNAL and character ROMs are ok. If you have an autostart cartridge does that boot correctly? Hi, i don't have any cartridge for VIC20, so i ordered diag cartridge (de...

Try this article https://sleepingelephant.com/ipw-web/bulletin/bb/viewtopic.php?p=75952&hilit=fault+diagnosis#p75952 Looks like you tried changing Character Rom, try changing Basic Rom Hi, thanks, but i mentioned in my second post that i tried that chip also. but no change! I have ordered diag ...

butjer1010 wrote: ↑Sun Jan 12, 2025 6:52 am Update:
Try to change Basic ROM from working one, no change!

Another update

tried to change UD8, UE8, UF8 and UD9 - no change!!!

Update:
Try to change Basic ROM from working one, no change!

Hi to all, i managed to get another VIC20 in very bad condition, but there is a hope :) It turns on, but instead of characters, there are only few blue squares on the screen (pic in attachment)! I tried to change sockets on CPU and VIC chip, 'cause they were very low quality for better ones, tried t...