As I continue to collect games, there are more and more problems I'd like to learn how to fix on my own. I picked up a logic probe a while ago, and I'm trying to comprehend the concept of checking IC's. I have a Crystal Castles that passes all of the RAM and ROM tests, but is screwing up when drawing/erasing the backgrounds and the gems on the screens.
Here's a video of the problem:
With some advice from bit_slicer, I started looking in the Bit Mode section of the board. I have the schematic pack so I know what IC's should be checked. I looked up some of the spec sheets for the ones I wanted to check. However, what I haven't put together yet is exactly what I should be looking for. From what I understand I need to check all of the inputs and outputs to see if they are high, low, or pulsing. How should I be looking at this? Should I list out the inputs vs the outputs based on the spec sheets and try to determine what the outputs should show depending on or/and for the chips? I just honestly don't "get it" yet on what I need to look for. Is this pretty tough and should I just give up, or is there some easy, common advice I can follow?
I hate to be such a newbie with aspects of this hobby since I've been collecting so long, but I guess I'm envious of some of you guys who can do some of this advanced stuff.
Here's a video of the problem:
With some advice from bit_slicer, I started looking in the Bit Mode section of the board. I have the schematic pack so I know what IC's should be checked. I looked up some of the spec sheets for the ones I wanted to check. However, what I haven't put together yet is exactly what I should be looking for. From what I understand I need to check all of the inputs and outputs to see if they are high, low, or pulsing. How should I be looking at this? Should I list out the inputs vs the outputs based on the spec sheets and try to determine what the outputs should show depending on or/and for the chips? I just honestly don't "get it" yet on what I need to look for. Is this pretty tough and should I just give up, or is there some easy, common advice I can follow?
I hate to be such a newbie with aspects of this hobby since I've been collecting so long, but I guess I'm envious of some of you guys who can do some of this advanced stuff.


