Silent Scope RTC data information

 General, Technical Info  Comments Off on Silent Scope RTC data information
Dec 182012
 

Today I burned a new Timekeeper chip for someones Silent Scope and since I had my board out for testing I thought Id run a few tests of my own.
I know with SS2 there is a checksum in the RTC data. This is not the case with SS1. It just has 13 bytes of data not all of which gets checked.
Here is what I found:

The first 8 bytes must read: 47 51 38 33 30 00 00 00 (GQ830 )
If any of this is different then you will get the 11p error

The next 2 bytes are the year. Mine originally read 20 00
It is actually the year thats shown in game on the title screen etc and can be changed to whatever you want, like this

The last 3 bytes must read: 55 41 41 (UAA). If this is changed to anything else then its 11p error time again.

From what ive tried you can add any data after this and it will make no difference.
The same data is also used across all versions of Silent Scope 1.

I will take a look at the SS2 data sometime too.

 Posted by at 1:39 pm

CPS1 Diagnostics ROM

 General  Comments Off on CPS1 Diagnostics ROM
Dec 152012
 

cal2 over on the Aussie Arcade forums has made some very useful CPS1 diagnostic software.

“Works only on a CPS-B-21 C board (with no suicide battery). Tested working on street fighter 2.
Tests work ram and vram (shared vram only, gpu vram cannot be tested).”

“Replace .23 with this rom”

sf211
Street Fighter 2 B-21

megama14
MegaMan B-21

Thanks to cal2 for allowing me to host these.

 Posted by at 9:13 am

Partial Rainbow Islands schematic

 General  Comments Off on Partial Rainbow Islands schematic
Dec 092012
 

Made these a long time ago to help me with a fault. They are far from perfect and it doesnt really cover a lot but it may help someone.

Rainbow Islands Schematics

Zabanitu has sent in his own schematic of the sound section from a Cadash board. He also says it applies to a Rainbow Islands board too (with a couple of minor differences).

Thank you very much to Zab for this. Hope it helps someone out one day.
Taito Sound Schematic Download

 Posted by at 3:13 pm

Jumping (bootleg) to Rainbow Islands conversion

 General  Comments Off on Jumping (bootleg) to Rainbow Islands conversion
Dec 092012
 

I’ve finally got around to uploading the files requires to carry out this conversion.
If you don’t know what this is then see the link below
CONVERSION

Pretty much all the graphics ROM’s will need to be replaced so make sure you have a healthy supply of EPROM’s.

Jumping Conversion.zip

 Posted by at 3:04 pm

Caveman Ninja repair log

 PCB Repair Logs, Repair Logs  Comments Off on Caveman Ninja repair log
Dec 092012
 

Where to start with this one.
My good friend brought this round a while ago with the fault of jailbars down the screen and no sound.
After messing around a bit we couldnt even get the game to boot on my setup no matter what we tried. He left it with me and ive been chipping away at it for a month or two now whenever I get time.
Ive finally got this thing up and running.
First this I found was two PLD’s, TJ-0 and TJ-1, were getting really hot.
As I have a couple of spare Caveman Ninja boards I did a swap and the game booted. Strange thing though, those PLD’s actually work in my other semi working board.
So now we have this

and no sound was present either.
Jailbars are usually a sign of a failed ROM so off the the tile ROM’s I go.
Found MASKROM MAG-02 had a few floating data pins. Replaced this for one off my scrap board and we get this

Graphics are back. Now onto the sound.
Looking first at the two OKI M6295 chips I could see neither of these were being enabled. If I pulsed the enable lines I could get various sounds to play. This tested the rest of the sound circuit so I knew it was good.
I traced the enable lines back to a 74LS138 decoder which wasn’t doing a great deal despite having what looked like good inputs. I removed this and it was indeed dead so replaced with a new one.

Still no sound though.
I could see the sound CPU and ROM were being addressed properly so next up was the RAM. On this board it was a TMM2063 chip. I could see activity on the data lines but it was struggling to drive them up to logic HIGH so removed that and that too failed a test.

I replaced it with a CXK5864 chip. Still no sound.

I started looking into how the sound section worked and found that the custom 104 protection chip is responsible for activating the sound.
I got in touch with a guy called Bryan who wrote the MAME driver and he gave me some nice information of its operation and basically pin pointed my issue to this chip.
At first I tried reflowing the pins but it made no difference so after a bit of debate with myself I took the plunge and removed the chip

I replaced it with one from my scrap board. WE HAVE SOUND!

And thats it, or so one would think. After about 2 minutes of playing this game, some of the sprites started to go a little crazy.

Going over the sprite ROM’s I found another one (MAG-06) with a floating data line. Replaced this with a spare and all is well once again.

Without a scrap board to take customs from this would have been one for the scrap pile.

 Posted by at 11:00 am