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Arcade King
7th February 2009, 09:59 PM
PCB looks like somebody had a previous shot at fixing the board(gun shot approach that is), so theres quite a few IC's already been replaced.

Board was dead with a blank screen blank screen. immediately found dead chips 74ls74(F) @ 4M, 74ls08(F) @ 5L, 74ls00(F) @ F7, 74ls273(F) @ 8H and 2 X 74ls367(GSS) hex buffers (colour) @ 8A and C (these things almost blistered my finger!.
At this point I've got a green screen with some random garbage for a few seconds when I turn it on.
I can't really find any other obvious fault at this point so I've decided to pull some of these Fujitsu 245's out to see if they come up good on my programmer. As I suspected H10 and 11 were both dead, replacing these the board boots up but im getting random crashes and garbage. Turning down the voltage I seem to get a longer run out of it. Looking at the schematics I decided to pull the 245 @ B3 although it tested ok once it warmed up it would fail. I'm starting to see a pattern with these (F)ucked) Fujitsu IC's so I'm going to replace the whole lot of the 245's just to play it safe, I know im only going to have to replace them down the track anyway.
After replacing all of them the game is up and running with no sound.

Starting to get shitty with this board fix one problem and another chip fails right in front of my eyes.

Problem: Missing red out of the lower half of the GnG title and weapon box at the bottom of the screen wrong colour.
Fix: bad 74ls174(GSS) @ 4F

Problem: board just died with green screen.
Fix: Bad 74ls174(GSS) @ C3

Problem: Colour in Topscore text is randomly fluctuating from red to white.
Fix: Another bad 74ls174(GSS) @ 8F

Problem: all the text and GnG title is split in half and showing the top half at the bottom.
Fix: ANOTHER faulty 74ls174(GSS) @ E8. Pin 2 was stuck open (high) Starting to see a pattern with these 174's

Ok board seems stable time to look at that sound.

The YM2203C's and YM3014's were both already socketed so this should make life easier. Probing around I noticed the inputs were dead on one of the YM3014's, removed the YM2203 connected to it and I had sound FX, replaced the faulty YM2203 and while I got the music back only half of it was there. Problem turned out to be the YM3014.

I don't normally spend so much time on a PCB but I beleve this game is worth saving.
As usual the majority of bad IC's were F chips but there were a few GSS's 174's in there also. Usually When an F chip dies the outputs just go dead so the GSS chips were a bit trickier to find.
PCB seems to be 100%, will leave on on for a few hours to make sure nothing else shits itself.

BTW you can interchange the top and bottom board on this bootleg with an original Capcom PCB.

More Problems updated 19/feb/09

Problem: Title Screen graphics (high scores etc) colours flickering.
Fix: Traced the problem back to a bad 74LS194(GSS) @ D11, Replaced the other 74LS194(GSS) @ D10 just to be safe.

Problem: Game runs for a bit then crashes, when you try to turn it back on your get a "vram is bad error"
Fix: sigh man by the time im finished with this board it will be completely rebuilt. Had a bad 74ls157 @ 5H, using the probe you could "hear" the chip failing. The outputs sounded sick, looked sick were sick. I ended up replacing all of the 157's just to be safe.

Problem to end all problems :x Game was running fine for awhile then died...again! Screen background covered in random garbage and foreground was mostly zeros (see attached pic no.2). When you turned on the board you could see the garbage in the background cycle like it was doing its self test so I assumed the program was running but halting with an error.
Fix: I spent 4 nights on this on and off the bloody thing was driving me nuts I couldn't put it down! (even though I said I threw it on my shit pile)
I decided to remove all the chips i had socketed which was all the 245's. I also removed all the roms, main MC68B09P CPU and the 6264 and 6116 ram's. I was convinced the problem was had something to do with the character video ram. I poked around the 6116 with my scope and noticed some of the address were doing nothing, Using the schematics I traced it back to a set of 3 74ls157s (all of which I ended up replacing). I noticed pin 14 which is an input of the 157 @ 5H was sitting high. Using my probe and the schematics I traced the input (AB0) back to see what IC's its connected to. I immediately knew there was a problem when I traced it back to an 74ls245 @ N6 pin 11 which had already been replaced, with the chip removed pn 11 was sitting high when it should have been dead along with the rest of the row of pins on the socket (pins 11-18). I knew there must be a short somewhere. Going back to the schematics I traced AB0 through to a couple of other IC's, a 74ls259 @ B9 (pin1) and a 74ls138(GSS) @ A3 pin 1.
The 259 was an Hitachi brand and IMO they are a very robust (ive yet to find a dead one on any PCB I've worked on) The 138 was however a GSS which has been problematic through out my repair. The 259 looks like it had been replaced previously so I went ahead and used my side cutters to cut pin one which is an input on the 138. Fired the board up and away she went! I really hate these sort of faults where an input shorts.
The 138 is part of the I/O Port so disabling it didn't stop the game from running. Replaced the 138 and the game has been runing for about 3 hours without a hitch.

Before I did this last repair I did replaced all the roms and CPU on the board, I noticed the Roms were getting VERY HOT to touch, not only the roms but the main CPU, the 2 Yamaha sound chips and the 245's were all hotter than they should be. Before finding the above fault I replacing all the Roms the board now runs nice and cool. I think this confirms this board had been spiked at some point. Even when I first got the board running the game would crash to a white screen at random, some time's I got an hour out of it other 10 seconds, anyway shes all fixed...for now :b

PS: I always try and replace faulty IC's with either Hitachi or Mitsubishi brad, I find these to be extremely well made.

Update: 21/2/09

Bloody thing developed another fault but really it was my fault for not replacing the IC anyway.
Problem: Character sprites colours all messed up (see attachment 3)
Fix: This was the last GSS branded 74ls174 @ H1 on the CPU board and stupid thing was I knew it was on the way out but forgot to replace it. As soon as i saw the graphics colours screw up I knew what the culprit was :b

GameDude
7th February 2009, 10:11 PM
Good stuff... I agree worth saving, thats why I spent a while repairing a single layer GnG a while ago.....

Since you had some bad GSS as well maybe this one got a harness the wrong way maybe JAMMA or upside down:unsure

Arcade King
7th February 2009, 10:23 PM
shit aye single layer? id like to see that.

Arcade King
19th February 2009, 09:00 PM
Updated original post.

Ps I really hate this board but was a good challenge.

Womble
19th February 2009, 11:01 PM
I spent 4 nights on this on and off the bloody thing was driving me nuts I couldn't put it down!

I know that feeling well, takes hours and hours but all the while you feel you are 30 seconds away from solving it all.

JasonC
20th February 2009, 01:03 PM
just out of interest AK, what did it cost to fix this board (not including labour)

regards

Jason

Arcade King
21st February 2009, 03:32 PM
Updated original post again.


just out of interest AK, what did it cost to fix this board (not including labour)

regards

Jason

Mate cost me $0. I'm lucky enough to have 3 large boxes of parts boards a lot of which was given to me over the years. Many many hours in labour though.

Hewitson
21st February 2009, 04:57 PM
Hmm I personally wouldnt be comfortable using used parts for repairs (unless its a custom, of course).

Womble
21st February 2009, 05:09 PM
The trouble is unless you do use used parts the repair is going to be costly. I have just set up a small set of component drawers for my TTL chips, RAM chips, ROM chips, CPUs. I have 40 individually labelled drawers and that's just for the common stuff, if you have to buy new every time you come across a dead chip its going to either cost a bomb locally if you can find the part anyway, or the cumulative postage for getting it all in dribs and drabs will end up costing you hundreds of $$. A repair that would also take a few evenings would end up running to months as you have to stop and start depending on when the parts arrive. Jaycar still sell some TTL chips but only the very very very common ones, and they cost a bomb there too.

A drawer full of scrap boards will provide almost everything you need, for free, and with zero delay, even some of the really weird rare TTL chips that you can't buy anywhere these days other than by mail.

Arcade King
21st February 2009, 05:19 PM
Hmm I personally wouldnt be comfortable using used parts for repairs (unless its a custom, of course).

I dunno why mate as far as I know theres no such thing as new as far as logic chips go and I personally don't consider NOS to be new. I've had NOS parts fail straight out of the tube, old is still old IMO.
I find you can't go wrong sticking to good brands like Hitachi pulls or not, I've never had a pull fail yet on any repair.

Hewitson
21st February 2009, 06:19 PM
Yeah I completely agree with both of you, however theres something nice about soldering in nice shiny brand new chips instead of used ones. Feels like you've done a better quality repair.

JasonC
21st February 2009, 08:10 PM
Updated original post again.
Mate cost me $0. I'm lucky enough to have 3 large boxes of parts boards a lot of which was given to me over the years. Many many hours in labour though.

thats tops mate
very impressive

dezbaz
21st February 2009, 09:28 PM
Hi Travis

I wonder if you are able to look at a River Raid EDIT (River Patrol) board for me (I have 2 actually)

I don't have pinouts, but I am stuck on working out the RGB and sync actually

Any chance you can have a look?

(Naturally I would pay etc)

Best Regards

Arcade King
21st February 2009, 09:34 PM
sure mate I can help you out. Best tools to work out a pinout is a logic probe or CRO or even better a schematic.

dezbaz
21st February 2009, 09:46 PM
sure mate I can help you out. Best tools to work out a pinout is a logic probe or CRO or even better a schematic.

I don't even know if it works, so pinouts are the first thing I suppose

I do have a logic probe (Maybe I should start a new thread for this??)

Hewitson
23rd February 2009, 05:07 PM
Apparently this game runs on the Crazy Climber hardware.

Pinout: http://www.ggdb.com/KB.aspx?c=Coin-Op&s=Arcade&vid=626&kb=55

dezbaz
25th February 2009, 08:34 AM
Apparently this game runs on the Crazy Climber hardware.

Pinout: http://www.ggdb.com/KB.aspx?c=Coin-Op&s=Arcade&vid=626&kb=55

It's 36 pin, but thanks for trying mate - Like Falcon, but it is a bootleg board

Prof
25th February 2009, 04:25 PM
Should be pretty close the the 18 pin crazy kong pinout. Used on a lot of pcbs, pheonix, naughty boy, etc.