1983 C64 Rev A up and running

By on Aug 23, 2015

I have been working on restoring and getting an old C64 breadboard version back in to a fully functioning state. The below screen shots show how the C64 was originally responding when powering on. All in all not very well. Garbage on screen Changed BG color and garbage Missing pixels Fault finding There are many helpful sites that tell you what different start up screens can mean and many issues are a result of bad DRAM chips. But since all the chips seem to use the same address and output lines there are many that could also create problems. However, first testing point is always making sure the power blocks for the C64 is producing the correct voltages on the correct pins. Since these are known to fail frequently and high DC voltages can wreck a machine very swiftly this is a good place to start. All is well with the power block.   DRAM With all of the sockets soldered I was...

Trying to get my old C64 working

By on Aug 9, 2015

Just removed all the RAM chips and awaiting new sockets before fitting the replacements.