Defective CPS3

[WRF77]

Hello, Can someone help me?

I have a CPS3 with original cartridge, CD, and SIM cards, and it's having a problem. When I turn it on, it's stuck on a black and white screen.

I tested the signals on the DL-2729 with an oscilloscope, and there are oscillating signals that seem normal. But the main bus signals, both address and data, are stuck at either low or high levels. I checked the signals on the DL-2829, and the signals coming from the cartridge are stuck at either high or low levels.

Could this problem be the cartridge having lost its key? What other problems could it be? How can I test the cartridge to determine if that's the problem?

 

[WRF77]

@cruzlink2, Could you give any clues about the problem?

 

[cruzlink2]

original cart hmm? so not darksoft? it could be suicided since your're getting no signals on the main bus. a board without a cart will hve no signals in the main board, if you're lucky its a dead cart if not could be traces or loose pins on either the CCU, GLL1 or IOU. at worst one of those customs is gone, but I am rooting for a dead cart. do you have another known workign cart to try?

 

[WRF77]

The board, when I turn it on without the cartridge, doesn't boot; it just shows a black screen. With the cartridge, it presents this problem. When you say damaged, do you mean it lost its encryption? The cartridge still has the battery and is at 3.6 volts. I don't have another cartridge to test at the moment; I'm buying a Darksoft one.

In any case, first we have to rule out the cartridge's functionality. If it's not a problem with the cartridge, would you have a test sequence to identify which IC is faulty?

Obrigado pela resposta.

 

[cruzlink2]

The board, when I turn it on without the cartridge, doesn't boot; it just shows a black screen. With the cartridge, it presents this problem. When you say damaged, do you mean it lost its encryption? The cartridge still has the battery and is at 3.6 volts. I don't have another cartridge to test at the moment; I'm buying a Darksoft one.

In any case, first we have to rule out the cartridge's functionality. If it's not a problem with the cartridge, would you have a test sequence to identify which IC is faulty?

Obrigado pela resposta.

Even if the cart has battery they suicide, especially if static electricity hits it.

 

[WRF77]

Okay, I'll wait for a new cartridge to arrive to test if the problem is the cartridge or the board. Thank you.

 

[WRF77]

@cruzlink2, I tested the board with another cartridge and it worked. But now it's showing a character RAM NG error. Which RAM types could cause this error?

 

[WRF77]

Foto error

 

[Ape Cosplay]

Character RAM is the one @1D are the ones @2D/5D, thanks @cruzlink2.
Could also be bad traces or lifted pins on the GPU.

 

[cruzlink2]

1D is sprite ram, 2D-5D is character ram and yes do not go changing ram first. First check all connections between the ppu and resistor networks and then resitor networks and ram. it could be connections of loose pins on the ppu.

 

[WRF77]

Thank you, I'll check it out.

 

[WRF77]

Problem solved. I resoldered the pins on memory chip D5 that showed signs of a cold solder joint.

 

[cruzlink2]

Problem solved. I resoldered the pins on memory chip D5 that showed signs of a cold solder joint.

Good work.