Mario Bros Repair Help

[r67055]

Hello!
I bought an untested donkey kong bootleg pcb.
I looked for a pcb pinout for it. Something was wrong. (I'm stupid, I didn't read the eproms) I made the Jamma converter. I messed up a connection on a pin. After switching on, Smoke..... The sound ic (MB3712) emits smoke. I looked through the Pinouts. I checked the wiring of the sound chip. If I remember correctly, there was +12V instead of -5V. I was not happy. I thought it wouldn't be a big problem, it's just the sound. I started to examine the lines. unfortunately, not only the sound uses the -5V level. I stopped searching for errors. Then the problem just didn't let me rest. I read all the eproms. It turned out that this is not Donkey Kong, but MARIO BROS. I would like to fix it.
Unfortunately, I always saw this picture.

 

[r67055]

I started to investigate the operation of the CPU.
Reset and Clock OK.
I read the eproms and the Main cpu contents did not match.
I replaced the 4 main cpu eproms.

 

[r67055]

I think that one of the MEMORY is not working. I started checking the lines. I suspect the -5V line. I would like to ask if I am right in thinking that this could cause the problem? Which chip could have gone bad? Are all the chips (IC) on this line dead?
HM10422 is the first thing I think of..... Unfortunately, I don't have such an IC. I don't want to buy unnecessarily. how can I check if it's faulty?

Thanks if I can help in any way...

 

[channelmaniac]

Check the DMA controller IC. A failure with it would cause the sprites and moving components of the attract mode screen to not show up.

 

[r67055]

Check the DMA controller IC. A failure with it would cause the sprites and moving components of the attract mode screen to not show up.

Thank you very much for your reply.
Could you tell me which IC it is? And how can I check its operation?
I will examine the pcb. Around the processor and memory.

 

[channelmaniac]

Look at the 40 pin chips in your picture. It's right there on it. Check its operation with a logic probe or by substitution (replacing it)

 

[r67055]

Look at the 40 pin chips in your picture. It's right there on it. Check its operation with a logic probe or by substitution (replacing it)

I experienced interesting things.
I started changing the CPUs.
If there are 2 working LH0080 in it, it won't start.

 

[r67055]

BUT.
If I take out one of the LH0080s, it still works as if the LH0083 was inside.
Could the LH0083 be faulty? Unfortunately, there is nothing else I can put in it. What can be its substitute?

 

[channelmaniac]

It's a Z80-DMA chip, not a Z80-CPU. When you put 2 Z80-CPUs in there of course it won't work. It's the wrong chip. Find someone nearby with a Z80-DMA chip you can borrow or buy.

 

[r67055]

there are many defective pcbs from which I can extract parts. but I don't know what type to look for. what is the Z80DMA chip type.

 

[channelmaniac]

Datasheet Archive is your friend.

https://www.datasheetarchive.com/?q=z80-dma

There you can find information on the Z80-DMA chip...

 

[r67055]

Datasheet Archive is your friend.

https://www.datasheetarchive.com/?q=z80-dma

There you can find information on the Z80-DMA chip...

Thank you very much for the information.
unfortunately, the link you sent is in German. If I understand correctly, it looks like the z80 DMA chip is faulty in this board. I couldn't find another similar chip. I see that Nintendo worked with this pairing. I can't find my donkey kong board. but I'm going to buy a z80 DMA chip and I'll let you know if I've tried it. Thank you very much for your help.

 

[channelmaniac]

Must be your location. It's in English for me.

 

[rewrite]

Must be your location. It's in English for me.

It's in German here in California.

Site isn't, but that PDF you circled is.

 

[channelmaniac]

There are other sites that carry PDF copies of datasheets.

https://datasheetspdf.com/datasheet/search.php?sWord=z80-dma

Is another one... took me 20 seconds start to finsih to find another source for the data sheet. To do advanced troubleshooting, you need to be able to Google "z80 dma datasheet" and grab the data sheets. They have pinouts in them which are crucial when you don't have schematics to refer to. (However, schematics are available for Mario Bros. online)

 

[r67055]

Thanks for all the information

 

[r67055]

the Z80 DMA has arrived. But unfortunately, nothing has changed.

 

[Darksoft]

I think the best you can do is to check the smaller chips, the 74LS with a probe and look for faulty ones. There are many tutorials online about how to check them. Probably one or more of these are bad. You should also check your RAM. That's what I would do.

 

[r67055]

I think the best you can do is to check the smaller chips, the 74LS with a probe and look for faulty ones. There are many tutorials online about how to check them. Probably one or more of these are bad. You should also check your RAM. That's what I would do.

You mean the RAMs belonging to the GFX Eproms, right?
Unfortunately, I don't know how to check this type.
How do I know which GFX Eproms 74xx I should start testing?

 

[r67055]

If I remove the 8-9-10-11-12-13 gfx eproms, the pcb starts as if they were not included.