C64 Breadbin Repair
Few weeks ago I purchased a new Commodore C64 with Assy. Board 250407 Rev. B from 1983. My guess was that this machine had not been switched on for decades ;-) Nevertheless the visual conditions from this nearly 40 years old computer were quite good: Top view Rear view Back view with connectors Side view After turning on the C64 this output was displayed: colorful mix of letters Mhmm, where could be the error? A good starting point is to measure the power inputs on the board: Measuring points, Source: forum64.de Blue = GND Red = +5V Yellow = +12V Nope, the input voltages are OK! Next it is a good idea to visit The Pictorial C64 Fault Guide to visually localize the error. So in my case it was hard to find a similar image, but after some research the best candidates are: PLA (U17) VIC II (U19) If you don't have working spare parts but an Arduino Uno there are a nice collection of test programs available ( C64 Test Tools fro