mv1a click of death

babeloued

New Challenger
Joined
Sep 27, 2015
Posts
52
hi
i just have a snk slot MV1A who have a problem,when i start it,i see a grabage screen wich click click on speaker,like watchdog
so i check the sp1 eprom look ok,the work ram ok ,backup ram ok,but i find one video ram destroy,so i change it but the same problem,i change the F0,neo buf near cpu,reflow all pin of lspc and mga but still problem
please if anybody have and idea to solve the problem:scratch::scratch::scratch::oh_no:
best regards
 

pnauts

Kuroko's Training Dummy
Joined
Jun 7, 2017
Posts
76
check your datas, adresses aren't cut, many components share this, LSPC-A0, PRO-C0, PRO-B0, NEO-E0, NEO-IO, NEO-G0
 

babeloued

New Challenger
Joined
Sep 27, 2015
Posts
52
merci pour ta reponse
j ai pas les pins des connections des lspc et autres chipset pour tracer mes pistes entre elle
peut tu me les donner pour que je verifie leur continuite sur slot MV1A
cordialement
 

babeloued

New Challenger
Joined
Sep 27, 2015
Posts
52
pour le chipset graphique c est un neo-grc ,et seulement neo-io existe dans la liste que tu ma donner pour les composants a verifier,les autres pas exitant sur ce slot
 

babeloued

New Challenger
Joined
Sep 27, 2015
Posts
52
hi
i prefer a list of pinout between more components for checking
like a backup error with method RAM1 RAM2 RAM 3 RAM4 and other components
are you a french?i ask you because i write with moliere language but you ask me in english
best regards
 

pnauts

Kuroko's Training Dummy
Joined
Jun 7, 2017
Posts
76
Yes I'm French but as we aren't on the dedicated subsection I'm keep writing in english.
can you upload a high res picture of the board ?
 

pnauts

Kuroko's Training Dummy
Joined
Jun 7, 2017
Posts
76
I saw NEO-IO, NEO-D0 and NEO-F0 on your pics (ZMC2 is out of concern for your issue)
and also this chips.

https://wiki.neogeodev.org/index.php?title=File:Neo-mga_pinout.png
https://wiki.neogeodev.org/index.php?title=NEO-BUF

The only way is to trace all the links between chips and Rams (mainly adress, data, Read, various write enable...)
it's a long job.
Do you have try various Bios (unibios, diagnostic, original) because you can have different results according to used roms, to begin the diagnostic one seems the more efficient.
 

babeloued

New Challenger
Joined
Sep 27, 2015
Posts
52
i try a few days ago but very long for check all traces,it easy if i have a list of pinout connectivity between chips together
i try all bios i have the original,unibios and smkdan diagnostic
best regards
 
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