xodaraP
Legendary
Hi,
I'm currently repairing a Cadash and wanted to start a repair log to keep track of my own progress as well as anyone who might run into a similar issue. Pictures to come later.
A friend sent me a Cadash board he bought, it's working pretty well, except the sprites are a mess.
I booted the board into test mode and straight away was given an object RAM fault
Before I desoldered the RAM (these boards are a nightmare to remove anything from) I checked the F244 and F373 above the object RAM to see what they're doing. Both have the correct signals so the fault isn't here.
I probed the RAM chips and almost all look fine on the scope, but one chip looks slightly different to the others, so I remove it. Sure enough it tests as bad.
I can see some corrosion around the RAM, which might explain why it's died. It also means when I remove it, I lose a couple of traces in the process, which I have to repair. I socket all 4 RAMs and repair a couple of other traces that are damaged.
Now the RAM is socketed, I just need to get replacement RAM of the same type and see where we end up. This is the current status of the repair.
I'm currently repairing a Cadash and wanted to start a repair log to keep track of my own progress as well as anyone who might run into a similar issue. Pictures to come later.
A friend sent me a Cadash board he bought, it's working pretty well, except the sprites are a mess.
I booted the board into test mode and straight away was given an object RAM fault
Before I desoldered the RAM (these boards are a nightmare to remove anything from) I checked the F244 and F373 above the object RAM to see what they're doing. Both have the correct signals so the fault isn't here.
I probed the RAM chips and almost all look fine on the scope, but one chip looks slightly different to the others, so I remove it. Sure enough it tests as bad.
I can see some corrosion around the RAM, which might explain why it's died. It also means when I remove it, I lose a couple of traces in the process, which I have to repair. I socket all 4 RAMs and repair a couple of other traces that are damaged.
Now the RAM is socketed, I just need to get replacement RAM of the same type and see where we end up. This is the current status of the repair.