Finally managed to fairly recently snag up a breadbin C64 for a decent price of 60€. Had to clean the keyboard as it was nasty and had a stuck key. Also noticed that Up doesn't work in Control Port 2. Need to channel my inner @adriansdigitalbasement.com and hope I can desolder CIA1 successfully 😄 - ThreadSky

About ThreadSky

Finally managed to fairly recently snag up a breadbin C64 for a decent price of 60€. Had to clean the keyboard as it was nasty and had a stuck key. Also noticed that Up doesn't work in Control Port 2. Need to channel my inner @adriansdigitalbasement.com and hope I can desolder CIA1 successfully 😄

Comments

adriansdigitalbasement.com•118 days ago

Are you sure it's a CIA problem? You would have issues with the keyboard if that were the case. Up on port 2 is Joy B0 which goes to PA0 (Pin 2) on CIA in U1. I would make sure you have continuity from the joystick port pin to PA0. Col 0 is on PA0 and you'd be missing several keys including RETURN.

alodnal.bsky.social•118 days ago

Yeah I did test continuity between the joystick port 2 pin 1 and U1 pin 2. Also tried manually grounding pin 13 on the KB connector but nothing happens. Grounding pin 19 works fine (down). Was kinda hoping it was a bad solder joint but sadly seems to be the CIA. It is weird that the keyboard works.

adriansdigitalbasement.com•117 days ago

That's an odd one, I haven't run into that before. One last test is try again with the joystick with the keyboard disconnected.

alodnal.bsky.social•117 days ago

Sadly didn't help. Thought I would just try desoldering both CIAs (hoping I don't make them worse) so I can try swapping them. Eventually i'll order a J-CIA. Thanks for your help though. This is my first time trying to repair anything and your videos have been a huge help and boost of confidence 😄

alodnal.bsky.social•98 days ago

Update on this. Finally managed to socket both CIAs (without breaking anything :D), swapped the CIAs around and the 2nd joystick now works. So indeed the CIA can have a weird failure mode where the KB seemingly works but a joystick button doesn't. Nice learning experience still :)

Posting Rules

Be respectful to others
No spam or self-promotion
Stay on topic
Follow Bluesky's terms of service

Comments

Posting Rules

Reply