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Neo Geo MV4F restoration - some community help appreciated

Oh and I started to use the logic probe and tested every pin of Z80, NEO-C1, D4990AC YM3016, 68k, YM2610 and NEO-DO. The results are:

Z80
  • PIN 6 CLK -> Light only ( I don't now what it means... it's not inside the documentation of the logic probe...)


NEO-C1 nothing on:
  • PIN 36 68k CLK
  • PIN 37 ROMWait
  • PIN 38 PWait0
  • PIN 39 PWait1
  • PIN 41 PDTACK

68K nothing on:
  • PIN 15 CLK


YM2610 nothing on:
  • PIN 27 ANALOG
  • PIN 34 GND
  • PIN 48 - 55 PADX
  • PIN 63 PHI M


NEO-D0 nothing on
  • PIN 18 XOUT
  • PIN 19 XIN
  • PIN 21 24M
  • PIN 22 68k CLK
  • PIN 23 68k CLKB
  • PIN 24 1MB --> Light only
  • PIN 27 12M
  • PIN 28 6MB
With nothing I mean neither Low or High and no sound form the probe. The documentation says that means it is not connected. I don't believe this and because I have no cloud, I need to compare it with my other board. Sadly I have todo this next week... I have no time to test more this weekend!!

Btw. this is the logic probe I use: https://www.amazon.de/gp/product/B006IRIP8I/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1
Maybe it is not good... and maybe this kind of testing is dumb! I thought I give it a try, nothing to loose.

I wish all of you a very nice and relaxing weekend!! Thank you for your help :-)
 
DeWitt said:
Thanks to you post @ack I understand now how I have to read the pinouts at wiki.neogeodev.org :-) Thank you very much!!!!

I tested every thing you sad. The strange thing is: NEO-C1 PIN 52 is not connected to 68K PIN 58. It is connected to NEO-G0 Pin 34 like described here for AES:
https://wiki.neogeodev.org/index.php?title=NEO-G0
Click to expand...
All 3 of the pins you have listed should be connected together, it's D11 (data bit 11) of the 68k (pin 58). A number of the components on the board will connect to the databus of the cpu, for example the bios (pin 7 on the bios is connected to D11 as well).
 
I understand! It was my bad, I used NEO-C1 PIN 53 for measurement... shame on me... I tried it this morning with a fresh mind and the connection is there. I'm sorry for that!

That means all connections you mentioned are there!

I also had a couple for minutes before work and checked all the 68k CLK lines. All traces are connected.
 
Hello, to everyone who helped me in the last couple of weeks or everyone reading this:)

I'm sorry for no updates last week... I got injured and currently can't use one of my hands. Noting that bad but it will take its time... so no no fixing or measurement these days... I can't even play games ;(

I'll be back 8)

Stay safe and healthy!
 
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