Hi, I am quite new to the C64 world. I have an Assy 250425 where everything works except up and right on Control port 2, as well as a few key combinations on the keyboard, tho all the keys work individually. My joystick works fine in Port 1. With a multimeter i checked continuity from the pins in the Port 2 to the respective pins on CIA 1 and they seem to all be working. My problem is I don’t have the tools to desolder CIA 1 without destroying it, but I am scared to destroy a chip that is actually working. Are there any other tests I can do to make sure it’s actually dead?
Before attempting desoldering, get hold of a C64 diagnostics test harness. Like this one: https://www.ebay.com/itm/134676125502
that’s a bit much for me for just testing one chip.