NBA Jam TE - setting up a 4 player?

ThomasM

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So I'm at the tail end of my NBA Jam restore and conversion. Converting from a two player into a 4 player cab.

At this point, my only issues are A) no sound. Worked before, just troubleshooting what the hell I did in the process and B) I can't get it to show up as a 4 player. I haven't wired the 3 and 4 player wires to the CP, but I have the harness's plugged into the 3/4 player slot on the board and flipped what I thought was the right switches, but no luck.

I'm working off: rev 1.0 01/17/94

Would it be a pcb battery thing or weird pin mapping? I think the battery on my board must be dead by now.

Thanks in advance!
 
Make sure you have the ribbon cable going to the sound board in the correct position. Red stripe goes on pin 1 on both boards. Not sure about the 2/4 player thing but it's possible you might need some different roms.
 
dipswitch for 2/4 player adjustment. don't remember which off hand. the sound board will still play the power on ding sound regardless if the ribbon cable is plugged in right or wrong. the ADPCM sound board requires a 50k ohm volume pot to hear sounds. the volume pot and test/service switch bracket are wired into the coin door harness, so if you unplugged that, you'll have no sound.

the more complicated failures will be in the capacitors on the sound board. they're at an age now where they will commonly fail.

verify the wiring harness from the main board to sound board is connected. if none of these help, PM me.
 
Thanks guys - I will double check all of those points tonight hopefully. It's strange as the sound was all working - I basically lifted it out of a previous working 2 player cab and not sure what I did - maybe the connector is off, but I did check it...And the sound +/- getting swapped wouldn't effect it would it?

And yes, right now my dip switches don't seem to be doing anything - any of them. Super weird. Would the pcb battery have any effect on them? I'll keep investigating - but nothing I do seems to bring up the 4 player options...
 
NBA Jam - sound issue

Haven't had a chance to dive deeper (also finding it hard to get my hands on an NBA Jam TE manual PDF?) but took a few quick photos in the hope someone can spot a stupid error.

- connectors all seem good from pcb to sound board and back
- volume is connected to a sound pot
- edge connector speaker +/- is heading up the speaker

Otherwise, not sure. Was totally working in the cab I pulled it from. So my guess is it's something stupid.

any help appreciated!
 

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Haven't had a chance to dive deeper (also finding it hard to get my hands on an NBA Jam TE manual PDF?) but took a few quick photos in the hope someone can spot a stupid error.

- connectors all seem good from pcb to sound board and back
- volume is connected to a sound pot
- edge connector speaker +/- is heading up the speaker

Otherwise, not sure. Was totally working in the cab I pulled it from. So my guess is it's something stupid.

any help appreciated!
The only thing I see that doesn't look good is the way you have that ribbon cable all twisted. I would check continuity on that cable. Are there any capacitors that look like they are leaking on the sound board?
 
look at the markings on both boards where the ribbon cable plugs in. the red stripe on both boards need to line up with the pins marked 1/2. it very well looks plugged in backwards on the sound board side.
 
Kev - totally hear you on that, but given that's how it was and it was working, I didn't mess with it! But I will check continuity if it gets to that point - good call.

mecha - thanks, I will check that out tonight. I had a quick look when I took the photos and didn't see any red stripe, but I will spend a bit more time tonight....

thanks
 
I'm looking at mine right now. The ribbon cable is on right.
50f6d75db34e0a92ce12b97fc7656c31.jpg
 
you don't need to check continuity on anything. I told you every single thing you need to know about the sound board. and the red stripe on the edge of the ribbon cable is obviously there, even in your picture. if you go into test mode, Diagnostics, Sound Board Test, and see a SOUND IRQ NOT DETECT error then the ribbon cable is plugged in backwards, as I've noted. you alternatively could've gone in to the Dipswitch Test and it would tell you exactly which dipswitch to change to enable 4 players.

I have nothing further to contribute to this thread. good luck.
 
Ok - appreciate the help and the frustration.

I will do more digging on my own and report back. Sorry to waste anyone's time.

thx
 
i can see from that picture the ribbon cable is backwards on the cpu board. See how on the sound board the red strip is at the number 2 screened on the board? See how on the cpu board where the two is screen is all grey cable section and the red strip is at the opposite end? Thats i always make sure mine are facing the right way, match up the red strip with the screen numbers on the board.
 
make sure you have -5 connected at the JAMMA connector. Without it I think the sound board will not work.
 
Hey guys - quick update. Checked out the above pts tonight and found that:

Sound:
- ribbons are connected correctly. Running the diagnostic on the sound board passed ok.
- Check that -5 is going into the Jamma connector from the power supply.
- Played around with the sound pot a bit, nothing

So no sound still - very strange. Any other tips on troublehshooting?

4 Player:
- I went into the dip switch test and was able to setup for 4 player. Interestingly, the switches differed from the one's I uncovered online

Thanks all
 
NBA Jam doesn't use -5 on the sound board. the CVSD and DCS boards before and after did though.

the dipswitch test won't lie.

see my first reply again.
 
I agree with everyone else I can see clearly in the photo that your ribbon cable on the one board is backwards -- not sure if you dont understand what everyone is saying but the grey cable with the red stripe (and not making fun of you - but its possible you legitimately are colorblind) is in the wrong position.. the red line on the cable is not at pin 1. If you fix that it should be working unless something else went out..
 

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I agree with everyone else I can see clearly in the photo that your ribbon cable on the one board is backwards -- not sure if you dont understand what everyone is saying but the grey cable with the red stripe (and not making fun of you - but its possible you legitimately are colorblind) is in the wrong position.. the red line on the cable is not at pin 1. If you fix that it should be working unless something else went out..
That pic is of my pcb and yes the red stripe is on pin 1, I'll post a pic in a few.
 
so I'm confused.

If I were to flip BOTH connections, the red strip would be at the opposite ends, not on 1 or 2.

When I run the diagnostic tool, the sound test passes. If the connections were wrong, as you are suggesting, the sound test would fail, right?

This was all working fine in the previous cabinet, and I haven't messed with these connections.

I actually think the problem is something else. A missed connection, or some other issue happening. This is my issue. I know need to start retracing or double checking stuff - as I think it's probably some low level dumb thing I haven't thought of.
 
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