Streetfighter 2 repair...

[Pledg]

I have a Streetfighter 2 PCB as a project to repair. (see attached pics)

To me the uneducated it’s a bootleg PCB, Groan! But I do stand to be corrected.
The main board is labelled as Streetfighter 2 but without any ROMS I can't confirm which version it is?
It has stickers labelling it 'Streetfighter 2 P4' and a fault sticker which appears to read 'player 2 down all the time'
The board has what I assume to be mask ROMS with codes so whether this gives a clue to the version?
There is a removeable daughterboard with sockets for 4 32pin ROM chips.

The edge connector has been thoroughly cleaned prior to making any connections.

I have the board connected for testing via a JAMMA harness and my GBS-8200 for video output to a TFT monitor.

The sound section of the board had missing caps when I received it which I have replaced and on power up I can hear the amplifier is working and I'm able to adjust the volume with the POT.

I suppose the first question which may seem stupid but I'll ask anyway. Should I get any sort of video output at all with missing ROMS on the daughterboard?

My ATX power supply is outputting 5.2v but as soon as is connected to the board I only get 4.1v on everything? Except one shift register chip (CD74HC597E) which is down at 3v?

I can confirm the 68000 CPU has a clock signal as does the Z80 in the sound section.

The board also has a PLCC chip and two adjacent 28pin dip sockets. I don't know what this section is for?

Any help with this repair would be very much appreciated.

 

[ekorz]

It’s a bootleg. I think it’s one of the “mstreet” variants like https://www.arcade-projects.com/thr...ampion-edition-bootleg-restore-upgrades.3409/ so there’s a lot of info out there if you search that name. YouTube has several repair videos as well. MAME layout but there are a lot of versions so it might not be 1:1.

Always measure your power system under load. Doesn’t matter what a psu is outputting when it’s disconnected, it only matters if the board is getting 5v on the 5v rail while it’s all connected. So you will need to turn it all on, measure the 5v rail, and turn up your PSU so that the board is seeing 5v.

But the missing chips are going to prevent boot anyway so start there. I think the ones near the 68k are the program roms, so absent the board won’t do anything. MAME has several versions dumped but yours looks like it was split across several smaller chips, so I'm not sure what the split / interleaving will end up being. The other missing chips look like they could be 62256 ram so that would also probably prevent the boot. Someone scavenged that stuff probably when the board stopped working.

 

[Pledg]

It’s a bootleg. I think it’s one of the “mstreet” variants like https://www.arcade-projects.com/thr...ampion-edition-bootleg-restore-upgrades.3409/ so there’s a lot of info out there if you search that name. YouTube has several repair videos as well. MAME layout but there are a lot of versions so it might not be 1:1.

Always measure your power system under load. Doesn’t matter what a psu is outputting when it’s disconnected, it only matters if the board is getting 5v on the 5v rail while it’s all connected. So you will need to turn it all on, measure the 5v rail, and turn up your PSU so that the board is seeing 5v.

But the missing chips are going to prevent boot anyway so start there. I think the ones near the 68k are the program roms, so absent the board won’t do anything. MAME has several versions dumped but yours looks like it was split across several smaller chips, so I'm not sure what the split / interleaving will end up being. The other missing chips look like they could be 62256 ram so that would also probably prevent the boot. Someone scavenged that stuff probably when the board stopped working.

Thanks for the info and links that's really helpful.
I didn't really want to try and increase the power at the board without confirming that was required. I can't up the power from my ATX power supply so will probably have to get a unit that has an adjustable 5v supply.
I have a TL866II programmer and some eproms so I am able to burn some ROMS but I'm a bit confused with what I should be burning. Do I only need selected parts of a ROM zip as some are already on the board? I can't seem to find any info regarding that.
I think I may have some RAM chips kicking around also...

 

[ekorz]

I am not sure what variant you have, especially since the program roms are the things that are missing. I can't find a 1:1 match between this and something dumped but you can go through the files and see if any of the labels & locations match perfectly. You need the 'main cpu' code burned onto chips on that sub-board. so perhaps this one https://github.com/mamedev/mame/blo...3cfdabb47205/src/mame/drivers/cps1.cpp#L10507 is a decent place to start if you're just winging it. to figure out which type of eproms to use you check the filesize on disc or in mame, confirm the pin count, and if you're stuck between multiple types you have to figure out where 5v and ground are and compare to the chips pinouts. that usually will tell you which variant is suitable. You're probably in need of two of each from this table but the pinout is going to tell you which one(s). Or four of the larger size, but doubling the binary so the code fills the chip.

 

[Xico77]

The sockets near the PLCC is for a pair of HM65256 (SRAM 32k x 8 ).
WIth no CPU roms, the board will not execute code, but usually it get in sync with the monitor, if the board isnt geting sync you could have problems in the clock\sync signal.
For the roms in the CPU section, the daugterboard problably splits a 40 pin 4Mb rom in 4, you can try to find a bootleg version with 4 roms in the CPU section, look in mame for the roms size of the dumps.
The board is almost the same as this one. (found in google)

I will search in my bin of broken bootlegs as i know i have some SF2 boots, and with luck i have one similar.

 

[Pledg]

I am not sure what variant you have, especially since the program roms are the things that are missing. I can't find a 1:1 match between this and something dumped but you can go through the files and see if any of the labels & locations match perfectly. You need the 'main cpu' code burned onto chips on that sub-board. so perhaps this one https://github.com/mamedev/mame/blo...3cfdabb47205/src/mame/drivers/cps1.cpp#L10507 is a decent place to start if you're just winging it. to figure out which type of eproms to use you check the filesize on disc or in mame, confirm the pin count, and if you're stuck between multiple types you have to figure out where 5v and ground are and compare to the chips pinouts. that usually will tell you which variant is suitable. You're probably in need of two of each from this table but the pinout is going to tell you which one(s). Or four of the larger size, but doubling the binary so the code fills the chip.

Thanks

I have 6 x 256kb M27C2001 Eproms to hand but I've only really burned single ROM replacements for the Amstrad CPC and BBC Micro in the past so I'm a bit clueless when it comes to burning arcade ROMs especially if I have to split files over chips etc. I've seen a few examples of the 4 chip daughter ROM board only having two chips populated but that's obviously down to file size etc.

 

[Pledg]

The sockets near the PLCC is for a pair of HM65256 (SRAM 32k x 8 ).
WIth no CPU roms, the board will not execute code, but usually it get in sync with the monitor, if the board isnt geting sync you could have problems in the clock\sync signal.
For the roms in the CPU section, the daugterboard problably splits a 40 pin 4Mb rom in 4, you can try to find a bootleg version with 4 roms in the CPU section, look in mame for the roms size of the dumps.
The board is almost the same as this one. (found in google)

I will search in my bin of broken bootlegs as i know i have some SF2 boots, and with luck i have one similar.

Thanks for the pic and info.
I've populated the two missing RAM chips so just the ROMs to burn now hopefully.

 

[Xico77]

This could be an overkill, but the daughterboard has a 74ls139 demultiplexer, probably to control the /CS of the roms, tracing the Inputs to the address you can try to know the size needed for the slots.

 

[Pledg]

The sockets near the PLCC is for a pair of HM65256 (SRAM 32k x 8 ).
WIth no CPU roms, the board will not execute code, but usually it get in sync with the monitor, if the board isnt geting sync you could have problems in the clock\sync signal.
For the roms in the CPU section, the daugterboard problably splits a 40 pin 4Mb rom in 4, you can try to find a bootleg version with 4 roms in the CPU section, look in mame for the roms size of the dumps.
The board is almost the same as this one. (found in google)

I will search in my bin of broken bootlegs as i know i have some SF2 boots, and with luck i have one similar.

Thanks for the reply.
I like to try and understand what components on the board are doing so is the PLCC chip a programable chip or a CPU as I note the board has 3 clock crystals?

 

[Xico77]

Thanks for the reply.
I like to try and understand what components on the board are doing so is the PLCC chip a programable chip or a CPU as I note the board has 3 clock crystals?

PLCC is the package, the IC is probably a programable fpga, trying to emulate the Capcom custom ic's for the graphics. The xtals are 1 for the 68k cpu, 1 for the z80 cpu and other for the dac (digital to analog).

 

[Pledg]

I have a ROM and the PLCC RAM installed but still no output other than the amp running.
The 5v supply is still down at 4.1v so I think the next step is to get an alternative PSU with an adjustable 5v supply before I do anything else with the board.

 

[ekorz]

It won’t boot without 5v that’s true. But you need to have programmed all main cpu roms on the appropriately sized and pinned chips as well. Did you find right sized and pinned chips? You said you only had 27c2001’s which are only valid for 2mbit data, and all the variants I see use at least 2x4mbit as well

 

[Pledg]

It won’t boot without 5v that’s true. But you need to have programmed all main cpu roms on the appropriately sized and pinned chips as well. Did you find right sized and pinned chips? You said you only had 27c2001’s which are only valid for 2mbit data, and all the variants I see use at least 2x4mbit as well

I'm still getting my head around your last message and need to get some 27C4001 eproms. Then I need to get my head around what I should be burning, it may take a few days for it to sink in but I'll get there!

 

[Xico77]

The roms problably are a combination of 27c010/ 27c020 / 27c040 I can bet it will be something like 1 x 27c040 + 1 x 27c010 and 1 x 27c040 + 1 x 27c010.
ekorz is saying you have to make sure the roms you burn are pin compatible with the roms the board is configured for, and looking for.
If you look in https://github.com/mamedev/mame/blob/master/src/mame/drivers/cps1bl_5205.cpp (Street Fighter 2 and other cps1 one board bootlegs) you can see most have on the CPU this configuration:

ROM_REGION( CODE_SIZE, "maincpu", 0 )
	ROM_LOAD16_BYTE( "3.ic172", 0x000000, 0x80000, CRC(11b5fe9 SHA1(6dda11e6c443a7c0ddf17a9840c93be00a424472) )
	ROM_LOAD16_BYTE( "1.ic171", 0x000001, 0x80000, CRC(6d948623) SHA1(0bcdda9ba2ef2051ad70277fbc383035a63540f3) )
	ROM_LOAD16_BYTE( "4.ic176", 0x100000, 0x20000, CRC(1073b7b6) SHA1(81ca1eab65ceac69520584bb23a684ccb9d92f89) )
	ROM_LOAD16_BYTE( "2.ic175", 0x100001, 0x20000, CRC(924c6ce2) SHA1(676a912652bd75da5087f0c7eae047b7681a993c) )

You can see this uses 4 roms for the CPU, 2x 512KB and 2x 128KB
1.ic171 (512KB) + 2.ic175 (128KB) and 3.ic172 (512KB) + 4.ic176 (128KB)

But I can be completly wrong!

Get some roms and a rom ereaser and start testing!

 

[Pledg]

So if I'm looking at the ROM set here I should be burning the two maincpu files, is that correct?
http://adb.arcadeitalia.net/dettaglio_mame.php?game_name=sf2cems6a

 

[Xico77]

If you want to burn that particular version, yes, you will need to burn 2 files:
ms6.u196 1.00 MiB 27c080 ?? 27c800 ??
ms6.u10 512KiB 27c040 ??

EDIT:
In the repair post of that board (MSTREET-6) you can see it have 2 42 pin mask roms near the cpu. if the files in mame are correct, they will be compatible with something like 27c800, 27c160 or 27c322

 

[Pledg]

If you want to burn that particular version, yes, you will need to burn 2 files:
ms6.u196 1.00 MiB 27c080 ?? 27c800 ??
ms6.u10 512KiB 27c040 ??

EDIT:
In the repair post of that board (MSTREET-6) you can see it have 2 42 pin mask roms near the cpu. if the files in mame are correct, they will be compatible with something like 27c800, 27c160 or 27c322

Thank you, the penny is starting to drop. I'll get hold of a selection different capacity eproms and have a burn and test fest!

 

[Pledg]

If you want to burn that particular version, yes, you will need to burn 2 files:
ms6.u196 1.00 MiB 27c080 ?? 27c800 ??
ms6.u10 512KiB 27c040 ??

EDIT:
In the repair post of that board (MSTREET-6) you can see it have 2 42 pin mask roms near the cpu. if the files in mame are correct, they will be compatible with something like 27c800, 27c160 or 27c322

So going back to my photo with the daughter board removed, would it be another option to discard the daughter board and install two 42pin DIP sockets and then just get 2 x 42 pin eproms???

 

[ekorz]

TL866II will need a 42 pin adapter and you’d program it in banks.

Then you’d either run a romset where the data is already combined, or you’d need to combine the data yourself.

And again you need to verify the pinout of the chip to make sure it’s correct. Grab a multimeter and figure out which pins are power and ground. Then look up the associated devices and sizes on that table I linked, and you’ll see which one has the ground and 5v in the right place.

 

[Xico77]

And removing a female pin header on a bootleg is a pain in the neck, sometimes the pins are too tight and can broke traces or vias when removed. The easy way will be confirm the size of roms needed in the daughter board, and try some releases, in the most part the roms are very similar, and in some boards only one rome are diferent.