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lancebung
17th September 2009, 07:43 PM
Hi guys

I purchased this board a few years from ebay, it was advertised as a street fighter 2 board if i remember correctly and was untested so had no idea if it was working enough. I picked it up for 20 bucks in postage so i wasn't to fussed if it worked or not. Anyway not having a working jamma cabinet for a couple of years I was unable to test it. I have just recently got my jamma cab working so i was able to test the board. As i suspected the board has a problem where it just shows up a red box. Having now seen pictures of street fighter boards i am fairly confident this is not a street fighter board.

I would like to make an attempt to repair this board but I have no idea what board it is so im stuck on where to start. I was wondering if any of the nice people at AA could identify this board?

If you need more pics i can attach some more, just tell me what you need.

Regards
Matt

Womble
17th September 2009, 08:54 PM
Am on a very small screen here but it looks very boot leggy to me, so it could well be SF2 and not look like anything you find online. Best bet is to dump and compare the roms.

dezbaz
17th September 2009, 09:01 PM
Looks like Jamma

Check your power entry pins, and if same as Jamma Fire it up and see

...............
Sorry, I read your post properly

This may be more helpful, I found a few this way - visually

http://www.crazykong.com/pcbs/

lancebung
18th September 2009, 07:49 AM
Yeah I have had a look at crazykong.com and could not find anything that looked the same.

I have not the knowledge nor the equipment to dump the roms and compare. Is this a straight forward process? Is there a website that shows how to do this.

When I plug this in it just comes up with a red screen. Any ideas what could be causing this? easy fix maybe or should i just cut my losses (20 bucks no big deal)?

Cheers
Matt

dezbaz
18th September 2009, 10:21 AM
Hi Matt

It could be worse, red screen is better than black screen.

A video rom may be gone. Check your voltages (using this diagram)
(http://www.dsbelec.iinet.net.au/JammaCabinetWiringDiagramTALL-HQ.jpg)
So is there any sound? Looks like there is a sound amp fitted to the board (1st pic top LHS)

Try turning the volume all the way up , then opposite direction and listen for sounds to try an identify the board, while it first starts.

If you have a logic probe you can see if there is anything happenning on the other video pins (On the Jamma Harness), ie the logic probes led will blink or flash on green or blue pin if there is any action. I suspect there wont be as the circuit before that may have failed, IE a rom Or some RAM is U/S

Dumping ROMS is done using a eprom Burner using software on your PC. A few guys on the forum can do it. Depends how much this board means to you


Could be a tough board to start on. Maybe buy a board with lesser probs, and move up from there. Pacman is the easiest board to start on, as there is 100's of sites with info on fixing them


Good luck, keep trying if you want.

My first post here was trying to get a qBert Bootleg's Sound Working. I had no idea, and kept trying and now it works. I learnt a hell of a lot

I have posted threads to get pacmans working and River Patrols too.

The guys here are great

lancebung
18th September 2009, 10:42 AM
Thanks for the info DezBaz.

I have not tried the sound yet as i have not hooked up the speaker in my cabinet (It is still a work in progress). The board doesn't mean that much to me as i only paid 20 bucks for it. I have brought it into work and had a bit of a look at it. I have found a few dry solder joints and some of the electrolytics look a little bit bulging so i have replaced them. I will see how that goes tonight, if there is no change i will prob just shelve it and move on. I have a logic probe so i may get back to it some day but i don't think i will need to trouble any one to dump the roms.

Cheers for the info again, i am interested in repairing a few boards and i think i will take your advice and start with a pacman or something with a little more info about it.

Cheers
Matt

dezbaz
18th September 2009, 01:15 PM
Good 1!

Threads like this are good to motivate others too (Like me :redface)

LOL

Hope to see you round

lancebung
18th September 2009, 06:23 PM
Ok so have had a bit of success with replacing the caps and touching up a few solder joints. The board is a Street Fighter 2 World Warrior as it now boots up. I guess like Womble said, it is a bootleg board.

There is still some graphical problems with it though, it has a red colouring to it and some of the grpaphics jump around a bit and have lines on through them. I will try and get some photos of it over the weekend to show you guys what is happening.

Any ideas on the red colouring through everything?

Regards
Matt

dezbaz
18th September 2009, 06:27 PM
Ok so have had a bit of success with replacing the caps and touching up a few solder joints. The board is a Street Fighter 2 World Warrior as it now boots up. I guess like Womble said, it is a bootleg board.

There is still some graphical problems with it though, it has a red colouring to it and some of the grpaphics jump around a bit and have lines on through them. I will try and get some photos of it over the weekend to show you guys what is happening.

Any ideas on the red colouring through everything?

Regards
Matt

Nice work, might have to wait for the pics to go from here

Are most of the ICs socketed BTW?

Womble
18th September 2009, 07:35 PM
The red colouring is probably caused by the loss of either green or blue signals, everything will look odd and red may be predominant now. Lines thru, and jumpy gfx can be bad roms or good roms in bad sockets. Removing and reseating all socketted roms can chase away many gremlins. Where in oz are you? Can give you a hand if you happen to be in melbourne.

lancebung
18th September 2009, 09:50 PM
I am located in Darwin so I am about as far away from Melb as you can get which is a bit of a shame lol. I will reseat the roms and see how that goes tomorrow. I will also take some pics as well.

Most of the IC's are soldered straight onto the board, there are only a few that are socketed (like 2 or 3 max other than the game roms).

Thanks for the advice, more info coming tomorrow :)

Cheers
Matt

dezbaz
18th September 2009, 11:54 PM
I am located in Darwin so I am about as far away from Melb as you can get which is a bit of a shame lol. I will reseat the roms and see how that goes tomorrow. I will also take some pics as well.

Most of the IC's are soldered straight onto the board, there are only a few that are socketed (like 2 or 3 max other than the game roms).

Thanks for the advice, more info coming tomorrow :)

Cheers
Matt

They are socketed as they have been replaced (probably) - IE a good practice

I look forward to pics

lancebung
20th September 2009, 04:23 PM
Ok I have taken a few photos which show some of the graphics problems. The whole screen has a red overlay as previously stated, but you can also see some of the blocky bits that show up in random places. There is also a problem where the horizontal alignment is out. It is all aligned when I load up other games so I think that is part of the problem and not just in need of adjustment.

Hope you can get more of an idea what is going on from the pics. I also have not reseated the roms so I don't know if some of this is due to badly seated roms

Regards
Matt

dezbaz
20th September 2009, 04:28 PM
Looks like green is playing up, some blue is present


Have you tried another PCB in the cab, to test the monitor? (I can't remember if you tried that)

lancebung
20th September 2009, 06:06 PM
Yeah my 2 other games (SSF2 and SFZ3) both work perfectly. Sometimes it will start up and the picture will be aligned well and then it will go bad again. It always has a red look to it though.

Since my last post I have re-socketed the roms and it made no difference.

Matt

SectionZ
21st September 2009, 07:44 PM
As the board sometimes comes up better then gets worse there could be a chip getting too hot. You can sometimes use 'freezer spray' to isolate it.

The blocks that are out of place are usually caused by bad RAM, but it could be 1 or more IC's.

Boards like this are not easy to repair, at least your on the right track :cool: old skool boards are a little easier to work with.

TheGuru
21st September 2009, 09:04 PM
I gather you mean the horizontal sync is out which causes the picture to look slightly bent or squashed. if it works perfectly try jiggling the harness. Most likely the JAMMA edge connector on the board is dirty. If it comes up good and then goes bad and your connector is clean it's a logic chip fault where it is getting warm and partially failing. Your colour fault is caused by some logic that has failed so the green is not being mixed into the video signal, or the green driver transistor on the board is bad. Some PCBs have 3 colour transistors and others use logic. It depends on the design of the board. You could try tracing the JAMMA green signal back to the 1st chip it connects to and change it (or check that chip is working if you know how). After that you'll need to trace the signal through the logic as it goes in and out of the various chips.

lancebung
6th October 2009, 06:52 PM
Ok i have done a little bit more work on this board today. I traced the green and blue lines back from the jamma edge to the first IC. They both went back to a 74LS273's and the red going back to a 74LS374. Looking the IC's I noted that the IC controlling the red looked like it was newer than the ones controlling blue and green. Also having no problem with red being displayed i decided to leave the red IC alone. I socketed and replaced the 2 74LS374's.

It looks like it has corrected the to much red problem but now it just boots up to a ram/rom check screen and freezes. It is saying that they are ok but it doesn't move on from this screen. Does anyone have any ideas on what could be stalling it. My next thing I was going to try was dump the roms and re-burn the data onto new ones and try that. I don't have the equipment to do this yet but i am keen to give it a try. Even if it doesn't fix the problem I am looking at it as a good way to get into the world of doing rom dumps and re-burning.

On that note does anyone know of a good priced rom dumper/ burner, all the ones i seem to find are fairly expensive. Im pretty new to this so im not even sure if the device that dumps the roms is the device you use to re-burn, but im keen to learn.

Any help would be greatly appreciated

Regards

Matt

lancebung
7th October 2009, 04:39 PM
Well I had a thought that i might have bumped one of the dip switches on the board and put it into a test mode. I checked the dip switches (assuming they were the same as a regular street fighter board) and they looked ok. I gave them a bit of a flick and tried the board again. It booted to the same rom check screen but didn't stall this time. The game booted up correctly and I could confirm that the colours are now all correct.

There is still the problem of the graphics jumping around a bit and blocks appearing in random places for a few seconds. Some of the backgrounds are also not loading and the sound is a bit scetchy. There is sound but some times it will cut out for a few secs or not play certain sounds. The game plays perfect other than sound and graphics issues.

I Cleaned the legs on the roms and reseated them again but that did nothing so im at the stage of dumping the roms and re-proggramming the data onto new roms to see if that fixes it. So im in the market for a good priced Eprom programmer if any one knows of a good one.

Regards

Matt