Hi! > > It looks like one of the data lines from the vic to the color ram is > > stuck to 0. > > Actually, from time to time the characters start flickering and it is > > possible to see dots or lines in the correct color. > > I have also seen that reading back the value in the color ram gives the > > correct value. > > This seems to exclude a problem in the ram itself. > > To me it looks like a bad connection between the VIC and the RAM. > > Do you think that the 4066 can be the reason ? All VIC-20s I've seen had very bad IC sockets. They've cheated me several times. So shouldn't it be a simple bad contact? I guess it's worth a try -- simply measure resistance between the VIC chip's pins and the socket pins (maybe enough to check the single databus pin you suspected). L. Message was sent through the cbm-hackers mailing list
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