MV2-01 COD fix.

pnauts

Kuroko's Training Dummy
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Jun 7, 2017
Posts
76
Hi, I have a MVS slot which had previously some click of death. I follow many traces to make me a matrix file of different links between components (and some had not a lot of information like PRO-C0)
I succeed in solving the issue of COD after wiring around +10s broken traces and changed 4 RAM chip (Fast 2K and slow 32K)
I wish not pollute any more the thread of smkdan (its diagnostic as well than the one of Razoola helps me a lot, thanks to people like them).
I'm now stuck in the crosshatch.
when I put a cartridge into the slot and check the 2 address for detection cartridge.

At 0100H it's good:



At 0182H it's not, the security code datas are good, but there is a shift in the address where it's supposed to be according to the wiki pages.

EDIT: Wrong previous sentence, it's good too, I have exactly the same values to the same address on a working set, but the cartridge doesn't start, stuck in crosshatch and no pad code buttons change the access to the menu.



thank you for your help.
 
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pnauts

Kuroko's Training Dummy
Joined
Jun 7, 2017
Posts
76
I put the Unibios ROM in a MV2 slot which works (with the same cartridge which works)
I view the memory with the viewer tool and I can confirm there is no shift, the memory is exactly the same that my 2 pics in the working and not working slot.
There is no shift and the game doesn't start.
Is the Unibios stay on crosshatch if the connector dedicated to the P ROM works and the one to the C ROM don't ?
other thing I have in mind, on the working slot when I look to the VIDRAM memory I have if I remind well something like.
00FF FFFF (profil repeat)
and on the bad slot I have only 0000 0000...
on the defective slot whatever I press any buttons setting, I'm always go to the hardware test crosshatch.
thank you for your help.
 

GadgetUK

Ace Ghost Pilot
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Sep 27, 2013
Posts
1,320
Could you clarify - are you getting the exact same behaviour on both slots?
 

pnauts

Kuroko's Training Dummy
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Jun 7, 2017
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76
Unibios+working slot+Puzzle de Pon

--> game start, unibios menu are accessible by holding buttons and memory map is like my 2 pics.

Unibios+defective slot+Puzzle de Pon

--> game do not start, unibios start directly to the crosshatch of the hardware test.
holding buttons have no effect but buttons interface works.
memory map is like my 2 pics.

I suspect a problem on the P ROM cartridge side
But does it explain the crosshatch ?
 

pnauts

Kuroko's Training Dummy
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Jun 7, 2017
Posts
76
Another point, I compared the working VRAM slot vs the no working VRAM slot (with the memory map viewer of the same unibios, same game).
According to this link

SCB1 data are different between the working/no working
FIX MAP data are identical between the 2.
Extension data are different between the w/nw.
SCB2, 3 and 4 data are identical between the w/nw.
 
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pnauts

Kuroko's Training Dummy
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Jun 7, 2017
Posts
76
Fixed !
NEO-F0(54) trace to AS04-6 was cut !
To do list: sound and slot 2
 

pnauts

Kuroko's Training Dummy
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Jun 7, 2017
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almost good V_V

IMG_20170718_194947.jpg
 

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Xian Xi

JammaNationX,
Joined
Dec 1, 2005
Posts
27,702
Check all connections to the ZMC2, the fact that only the C rom data is affected, it points to the ZMC2.
 

pnauts

Kuroko's Training Dummy
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I think I checked already all the traces but I'll check again.
thank you for your help.
 

pnauts

Kuroko's Training Dummy
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I haven't some spare parts.
here what I check with oscilloscope

pin1:"1"
pin3:"0"
pin4:"1"
pin5: pulsing
6:"0"
7:"0"
9:weird state
10:"0"
11:"0"
13:"1"
14"0"
12MHz: ok
and look some datas looks like pulsing.
 
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pnauts

Kuroko's Training Dummy
Joined
Jun 7, 2017
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76
I'll think I'l keep this one for spare parts.
I give a try with another slot.

graphics are fine in slot 1 and there is a an issue on slot 2 with 2 pixels columns.







Traces are good, I think one NEO-257 input is dead, I have to put a scope on this to confirm.
I have very low audio on headphones, then nothing, I think a recap will be fine but as I have a Z80 error with original bios, I bypassed with unibios and so is it possible to have audio working with a Z80 error detected with original bios rom?
And the last curious thing, Bios display is garbled with OEM and Unibios, I think SFIX is corrupt, is it possible or could it be another reason? (no bad traces on audio pipeline)
 
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pnauts

Kuroko's Training Dummy
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Jun 7, 2017
Posts
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Input NEO-257@L4 (54) short to Gnd is responsible for this trouble above. I'll fix it later.
I focus now on the Z80 error.
I have this report (sorry but the SFIX ROM seems also to have damages, others fix graphics are good, I'll check it later)



measures below are made with this display message "hardware test failed Z80 system" with unibios

the /CS on the SM1 (pin 22 of the 27C1000) is accessed repeatly for around 2ms along with the datas for the same time.
The /OE on the SM1 is always pulsing.
The /CS on the BR6116 SRAM is access for the same length but complementary, when ROM is accessed SRAM don't.

If I force to AES I have this message.
 
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