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Dead Side Arms PCB...

nam9

nam9

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Hi :(

Picked up a Hyper Dyne Side Arms PCB recently. Arrived...hooked it up and...nothing. No picture, no sound.
Board i receiving 5v all over, turning up the on board volume gives a hiss of silence suggesting the audio section is live, but not fed any input.
I guess here is where I start: How to fix PCBs - A Beginners Guide.

Since nothing works... I guess i should start with the clock and take it from there?
Problem... This is the CPU (my guess...) custom chip... any source on a pinout...?

2016-11-20 11.46.15.jpg

Also looking for some info on the crystal...but neither serial number give me much to work on.

2016-11-20 12.29.02.jpg

The crystal has 4 through hole leads, 2x5v (Vcc & output), 1x Gnd & 1x0v (probably E/D).
Without oscillator to test there isn't much else to say...

Anyone with this board have any suggestions?

Send it back is the obvious conclusion.. but it will most likely be junked as the seller admit they don't know much beyond playing the games. :(

A repair is most likely well over my competence level, and more so just cost prohibitive too..
 
Check the crystal is getting voltage and if you prod it with a logic probe it should at least give you something if it's not completely dead. From there you need to find the clock line to the CPU, reset line for the CPU and go from there
 
Ok, probed the first Z80:

Power, check.
/clock: high.
/reset: high.

HHHHHHHHHHHLHLHHHHHH
4039383736353433323130292827262524232221
1234567891011121314151617181920
HHHHHHHHHHHHHHHHHHLL

Z80 #2:

HHHHHHHHHHLHLHHHHLHH
4039383736353433323130292827262524232221
1234567891011121314151617181920
HHHHHL----H----HHHHH
 
Ok so both CPUs are high on clock and reset lines? If that's the case then the CPUs are both running, which is great news because we can move on

Next step is to see if you have sync, find the sync line on the edge connector and probe that and see what you get

Also I forgot to ask earlier, are you using the correct wiring connector? I can't remember if Side Arms is JAMMA or Capcom specific but make sure you're using the correct adapter if required. You're not going to get anywhere and can potentially cause damage if the wiring is incorrect.
 
Cheers! I'll check that out next.
Board should be JAMMA (its marked as such). Jamma edge from the manual:

2016-11-22_16-46-59.jpg

Link
 
nam9 said:
Since nothing works... I guess i should start with the clock and take it from there?
Problem... This is the CPU (my guess...) custom chip... any source on a pinout...?

2016-11-20 11.46.15.jpg

too..
Click to expand...

This is not the CPU but the a custom sprites generator.As already said you should check what the main Z80 CPU is doing.
 
Cheers caius. I had no idea what that chip was. Tested out the Z80s but they seem to be operational.

Tested the RGBSync lines on the jamma edge. Red & Sync are both low. Green & Blue are floating.
 
nam9 said:
Cheers caius. I had no idea what that chip was. Tested out the Z80s but they seem to be operational.

Tested the RGBSync lines on the jamma edge. Red & Sync are both low. Green & Blue are floating.
Click to expand...
You said CPU clock = HIGH and sync = LOW, but what are you using to measure these?
You said you have no oscilloscope, and that's understandable, but I hope you are using at least a logic probe. Both pins should be doing something instead of staying stuck. A logic probe would give you both levels at the same time. A multimeter would give some mid-voltage for CPU clock and almost 5V for sync, but according to what you state I get the impression that they are stuck.
If CPU clock is seriously stuck high and sync is seriously stuck low, then replace the oscillator X1 with another 16MHz one. Chances are, that the problem is right there or around it in the clock divider.
Also, there might be another part on the other board labelled 14.318MHz or something similar. You might want to check that as well.
While you are there, can you shoot photos of both boards so we can look at them?
 
Top PCB. Lower section will be mainly game data? I'll take a pic of that later.
I have a Mastech MS8211D logic probe which reports the 0v-1.5v "Low", 3.5v-5v High"

2016-11-21 23.53.19.jpg
 
That Mastek MS8211D looks more like a multimeter to me, honestly.
I am even more convinced that your clocks are stuck, but without a way to see at least if a pin is oscillating we are "blind": unless somebody else has already experienced this exact issue and therefore already knows the solution, the only way out is to replace the most likely suspects by trial and error.
I've had a look at the schematics and found that all clocks are derived from the master 16MHz oscillator at X1. Considering that the audio cpu should run at 4MHz I would try and replace: 74LS367 @ 14L, 74LS74 @ 15L, 16MHz oscillator @ X1. Although the board looks in mint conditions, you might want to look around for suspect traces around said components; maybe there's a tiny fracture somewhere. Also, don't forget to check the conditions of that small green capacitor soldered onto the pins of the 74LS367 @ 14L: it looks bent to the side and its pins might be broken or short-circuited with one another.
I hope this helps. :)
 
Any thoughts on a drop-in replacement for the crystal? UXO-122B &/or UNO 86B don't give me any hits... (see first pic).
I have found these on eBay... There are cheaper options, but I usually assume the less generic looking, the better the quality...
 
For crystals & oscillators, the lower the drift (expressed in "ppm"), the better the quality. You would need a datasheet to check this parameter; but oscillators are typically more stable than crystals anyway, so you are probably fine with whatever you buy. But ensure it is exactly 16.000MHz rather than a very close value. The one you found looks nice, also pricewise. It's probably NOS parts.
 
Oh...

2017-02-03 22.10.46.jpg

!!!

2017-02-03 22.07.29.jpg

(Thats just the camera effect on the sprites..)

Side Arms!
 
nam9 said:
Oh...

2017-02-03 22.10.46.jpg

!!!

2017-02-03 22.07.29.jpg

(Thats just the camera effect on the sprites..)

Side Arms!
Click to expand...
Gr8
I'm glad you managed. However your oscillator sure has taken quite some time to get delivered....
 
Took me a month or more to get oscillators the last time I needed a specific one (I think it was 16mhz actually) as the only seller I could find was in Israel

Regardless of time frame for delivery, the internet rocks - when most of these boards were built I would've been completely stuck if parts weren't available locally. Even chain stores wouldn't have been able to help back then since they would only have been able to call other stores to chase up a part they didn't have.
 
xodaraP said:
Took me a month or more to get oscillators the last time I needed a specific one (I think it was 16mhz actually) as the only seller I could find was in Israel

Regardless of time frame for delivery, the internet rocks - when most of these boards were built I would've been completely stuck if parts weren't available locally. Even chain stores wouldn't have been able to help back then since they would only have been able to call other stores to chase up a part they didn't have.
Click to expand...
I know EXACTLY what you are talking about! ;)
 
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