Help Me Obi Wan(s) you're my only hopes? (Another Star Wars problem.)

Madaracs

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Help Me Obi Wan(s) you're my only hope(s)? (Another Star Wars problem.)

Short history:

Bought the game two weeks ago.
Worked ok for about an hour then the graphics would do something like this:

download.jpg


Asked around in the forums and someone suggested it might be the AVG.

Replaced the AVG. Nothing seemed wrong but the problem with the graphics not drawing correctly came back.

A new problem has occurred:



As you can see there are no Tie-Fighters, Death Star or Fireballs.

Also note in the video that the Death Star(s) at the start screen are not drawn as complete circles. It's a little messed up around the edges.

Here are screenshots from TEST mode:

IMG_0385.jpg


IMG_0386.jpg


IMG_0387.jpg



As many have been, I'm totally new to repairing Star Wars boards and would appreciate any help. Or if anyone knows somebody I could work with on getting this repaired it would be really great.

I do have the manual too but I'm a novice at electronics. I am OK at soldering though.
 
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I'm guessing it's a board issue of some kind but if you have not yet done so check your voltages coming from the power supply. I have seen some really strange things happen when the voltages go bad. Worst part is the bad voltages can damage the board then you end up with more issues.
 
No Tie fighters, and DS is typically a problem with the 4 proms I would try cleaning and reseating those first.
 
You picked that up, nice, maybe I should just drop the Dragons Lair off at your place so I can play your SW for a little while....after you fix it of course :) Good luck man!
 
You picked that up, nice, maybe I should just drop the Dragons Lair off at your place so I can play your SW for a little while....after you fix it of course :) Good luck man!

Thanks! I'll give you a shout later today. Going to be out at Ax-Man and places to get some caps and whatnot.
 
Are we talking the logic proms?

prom.jpg

Yeah the proms in the first pic. If you had problems with the eproms that should show up in self test.

Unfortunately I have only work on about 6 SW boards. So im not 100% sure which proms handle those graphics.
 
Thanks for starting this thread. I'm sure it will help me on the SW project I'm working on.
I noticed the starfield is missing too. And it is not going into the trench sequence.
Good luck on getting it going.
 
Thanks for starting this thread. I'm sure it will help me on the SW project I'm working on.
I noticed the starfield is missing too. And it is not going into the trench sequence.
Good luck on getting it going.

Interestingly enough, someone on these forums has already had a _very_ similar issue.

http://forums.arcade-museum.com/showthread.php?t=192913&highlight=74LS299

I'm pretty sure I'll be able to fix this board set. It will just take some time as I order parts.

In addition to the problem I'm dealing with I discovered an exploded cap and corrosion on the sound board. I've removed all of the 35V 100mf caps and re-capped the sound board. So at least I know that won't be an issue as it seems to work fine.

I'll have more info later in the week when I receive my stock of 74LS299 chips that I ordered today.

I'm going to dump the PROMs and the EPROMS as well.

Unfortunately, it looks like MAME only archives a version of Star Wars that I don't have so the checksums mayn't match up. On the other hand, my buddy who works on the MAME team would like to dump my chips if they're good--and that would be rad.

More to come...
 
Just re-read this post, and there is a Matrix error. B 0000

Not sure exactly what that means, but I think that the B accumulator is not loading.
 
Hello all.

So the shotgun approach didn't work but now my board has a couple of new socketed 74LS299s on it. (7D and 7E I believe) Which is kind of cool but it didn't fix my problem like it did the other gentleman that had encountered no stars or tie-fighters in game play. With the complexity of the Matrix circuitry and such, I'm sure there are many more ways to have this problem manifest itself but it was worth a shot!

I'm going to use the Star Wars Troubleshooting guide to see if I can isolate which part of the board is the issue. Since I only have a single Matrix error (B 0000) in the normal test screen, it could be easier to track down with the guide than others... but we'll see.

I had an seasoned operator friend of mine over last night and we read over the schematics for the Matrix portion of the board and in addition to any of those sections on the board he thinks it could be the non volatile RAM or the PROMs.

Another friend of mine is building a reader for the PROMs so we can see if their checksums match up with what are stored in the MAME project.

There is a guy named Clay on here that has done a number of really awesome mods for the SW boards and the WG6100 and other games--I was hoping he produced a PROM replacement board but I don't know that anyone had bought them.

The other option I was thinking of was purchasing an ESB upgrade kit because that looks like it has PROM replacements in it.

Wish I had another board so I could Frankenstein something together...

The saga continues...
 
The 4 Proms are suspect in every SW thread it seems. But it Looks like you lucked out with a cleaning and couple of eprom/IC leg repairs. Hmmmm...
 
Well, it wasn't the four Proms. So that's good. I've got two sets of those now--which makes me happy.

The 16 beeps are all good too so I can assume that the EPROMs are good I'm told.

The next thing is to use the Star Wars Troubleshooting guide to run through the Matrix error tests and see if I can isolate the problem area on the board.

Gonna check voltages today too if I can.
 
I checked all of the voltages. They were all good. (~4.9 on +5 and -5 and ~11.9 on the 12V leads)

Because of the self tests, I know the EProms are good and I did the self test on the NOVRAM as well which was good also.

I checked every trace and solder joint with a magnifying glass and found nothing.

I pulled, checked, and reseated all of the socketed chips on the board as well.

For the B 0000 error, my suspicion is now some other chip is at fault but when I attempted to start running through the Star Wars Troubleshooting Guide's Matrix Troubleshooting section, I was unable to get the first test to complete correctly.

It says to turn all of the dipswitches at 10D to the off position and ground the test point on the main PCB. The result should be that the 3 LEDs on the board light up for 10 seconds, then switch off while the 1st LED continues to blink. This never happened. They all just blink once, stay on for a second or two then turn off.
 
I checked all of the voltages. They were all good. (~4.9 on +5 and -5 and ~11.9 on the 12V leads)

Because of the self tests, I know the EProms are good and I did the self test on the NOVRAM as well which was good also.

I checked every trace and solder joint with a magnifying glass and found nothing.

I pulled, checked, and reseated all of the socketed chips on the board as well.

For the B 0000 error, my suspicion is now some other chip is at fault but when I attempted to start running through the Star Wars Troubleshooting Guide's Matrix Troubleshooting section, I was unable to get the first test to complete correctly.

It says to turn all of the dipswitches at 10D to the off position and ground the test point on the main PCB. The result should be that the 3 LEDs on the board light up for 10 seconds, then switch off while the 1st LED continues to blink. This never happened. They all just blink once, stay on for a second or two then turn off.

I shall be following your progress for this thread as I, too, am getting the B 0000 matrix error on the SW board I have in my machine currently (just noticed this last night).

I get a ROM3 error at the main self test screen. I have the VectorLabs multikit installed, so I do not have the original ROMs nor the PROMs seated on the board any more so my first step will be to uninstall the kit and see what happens. I will try to do this tonight.

FYI, my symptoms are that the vector graphics for when a tie fighter is shot and breaks apart are messed up, and the asteroids graphics in ESB are also messed up. Everything else works fine.

I have a second board set with Clay's older SW/ESB kit installed that works fine so I can still enjoy my game, but I would like to fix this problem on the other board of course :) .

Hopefully you'll be able to fix your issue, and in turn that will help me out ;) . I'll also post if I have any success.

Jon
 
http://falz.net/files/starwars/troubleshooting_guide/

Is this the Star Wars troubleshooting guide you are using?
If not, lots of helpful stuff on this page.
Jim

[Edit Edit] Yes, this is the one. I tried this test:

Main PCB Microprocessor and Memory Test

The following test determines whether the 68B09E microprocessor, ROM 4, and program RAM on the Main PCB are working together to enable the basic Self-Test and Hardware Diagnostic Tests to be performed.

Test 1
Perform the Preliminary Procedure under Hardware Diagnostic Tests.
Set the option switch at location 10D on the Main PCB as follows:

8 7 6 5 4 3 2 1
OFF OFF OFF OFF OFF OFF OFF OFF


- NOTE - If Test 2 was performed just prior to Test 1, omit part 3 and proceed to part 4.


Momentarily ground the RESET test point on the Main PCB. LED 1, 2, and 3 should all light and remain lit for about 10 seconds.
If the microprocessor is running, LED 2 and 3 will extinguish and LED 1 will flash on and off about once per second. LED 2 and 3 must be off; if not, the microprocessor may be running in a failure mode with the RAM and ROM not working.
LED 1 will be set to flash (or not flash) depending on the results of the test, and will continue in that state until another test is selected or the RESET test point is grounded. For example, if something happens after the test that either corrects the faulty program RAM or causes a malfunction, the diagnostic program will not recognize it and LED 1 will continue to flash (or not flash) until the RESET test point is grounded to repeat the test again.
If the microprocessor is not running, disconnect the Sound PCB or the AVG PCB. If the microprocessor begins to work, the problem may be a short on one of the address or clock lines on the Sound or AVG PCB.
If the problem still exists, refer to Troubleshooting With the CAT Box for checking the Sound and AVG PCB.

But I couldn't even get that test to run. So I kind of gave up.

Also: In talking with a guy over in Mass. who has worked on these things for 30 years, he seemed to think that I might be having a problem with the multiplexer that feeds the Math RAM at 5F and 5H. He told me to pull those socketed chips, check their pins and then check the multiplexer (74ls157) itself.

[Edit]

Here are some replacement chips that are listed for the 137211-001:

137211-001 IC,SRAM,2Kx8,150ns,NMOS,Tri,24pin,Pwr-dn,Plastic NEC uPD4016C-3
137211-001 IC,SRAM,2Kx8,150ns,NMOS,Tri,24pin,Pwr-dn,Plastic TOSHIBA TMM2016P
137211-001 IC,SRAM,2Kx8,150ns,NMOS,Tri,24pin,Pwr-dn,Plastic SYNERTEK SYP2128-3
137211-001 IC,SRAM,2Kx8,150ns,NMOS,Tri,24pin,Pwr-dn,Plastic AMD AM9128-15PC
137211-001 IC,SRAM,2Kx8,150ns,NMOS,Tri,24pin,Pwr-dn,Plastic FUJITSU MB8128-15P

Pulled from this: http://www.jmargolin.com/schem/atariavl.doc
 
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