SOLVED - Mario Brothers Missing Digital Sounds - New One

[SCUBA King]

It does seem like the MCU isn't running... can you measure the voltage at the RESET pin (pin 4) of the M58715? The reset pin on the CPU has different voltage thresholds than most I/Os (not TTL). Valid low is <0.6V, valid high is >3.8V. So, if you've seeing somewhere in the middle (e.g. >2.0V, which would be valid for TTL), the MCU's behavior isn't guaranteed, and could still be stuck in reset.

DogP

Roger that. Will take a poke at it when I get home tonight.

 

[SCUBA King]

It does seem like the MCU isn't running... can you measure the voltage at the RESET pin (pin 4) of the M58715? The reset pin on the CPU has different voltage thresholds than most I/Os (not TTL). Valid low is <0.6V, valid high is >3.8V. So, if you've seeing somewhere in the middle (e.g. >2.0V, which would be valid for TTL), the MCU's behavior isn't guaranteed, and could still be stuck in reset.

@DogP Pin 4 is coming in at 3.883v

 

[SCUBA King]

After doing everything I could think of I got some help from the man, the myth, the legend @jrok
After going over pretty much every single possible scenario with a LP and DMM he found the problem.
Pin 40 on 5L (8035) was getting 5.15vm but as soon as I put 8035 back in the socket it would drop to 400mv.
Tried 2 other 8035s, same thing.
Re-Socketed it, same thing.

Ohmed out pin 40 to 5v rail and got a crazy reading.
Then I couldn't get continuity between pin 40 and 5v rail
Flipped board over and the tiny little solder spot filling in the hole from front (where pin 4 connects to 5v rail through hole) and pin 40 wouldnt tone.
Fired up the board, bridged those two points and sounds worked.
was going to jumper but decided to reflow that through hole only, and I got a tone.
Added a tiny bit more solder, took it back down to test bench with no jumper, plugged it in and got 5.15v at pin 40. Then installed 8035 and got sounds on boot and 5.15v at pin40 on 8035.

Mario is back in business.

I am guessing that when I got this board with dead digital sound originally, I either disturbed or hakko'ed that through hole when I did original socket job by mistake.

Not sure how it happened, but either way, it is fixed now, I wanted to document it here for others and thank @jrok for taking the time with me tonight once again.

Mario WB is back in business!!!!!!

pics below

hakko tip cleaner pointing to brought hole I reflowed.

Side cutters showing two points I bridged to get sound back by bridging pin 40 to through hole before reflowing.

 

[SCUBA King]

These sounds are controlled by the main cpu so the sound cpu section is probably fine.

The picture with the red and green line is the walk sound circuit. Are you getting pulsing at 2H Pin 2, 10 when the walk sound should be playing? Since you are getting other sounds im guessing it is, so id check that 1H, 1K, 2K are working as they should. IIRC if there was battery damage on the board sometimes this area gets damaged. If theres no pulses then 4C is probably dead.

The picture with the blue line is the skid sound circuit. You should be getting pulsing on both sides of 7L Pin 8, 9 when the skid should be playing. 3H pin 10, 7, 1 should be constantly toggling. If thats fine then you can check that theres a pulse coming from 4L pin 13, and that 1K, 2K, 4J are correct.

1K and 2K are common between these two circuits so id suspect those.

Necro bump my own thread for analog sound missing. @Muffindude am getting all sounds except mario walk. Analog circuit all checks out. I feel like the command to call the sound isn't being sent. 2H pin 2,10 no pulses when mario walking.

4C pins 14/15 both pinned high

Just for fun notes : z80dma has been socketed (not by me) and replaced.

Even more fun, if I touch pin 7 of 123 at 2D with logic probe, the board resets.

Any guidance is appreciated. Also if there is a full mario schematic somewhere, the copies I found are all hacked up. I swore I had a full set somewhere but I didn't find. I think I actually plotted it bitd ??

 

[Muffindude]

This one has the full schematic: Manual
What happens if you lift pins 14/15 from 4C, does it go low? If you short 2H pin 2 to gnd does it make the sound?

 

[SCUBA King]

This one has the full schematic: Manual
What happens if you lift pins 14/15 from 4C, does it go low? If you short 2H pin 2 to gnd does it make the sound?

Will report back tonight when I get back to the bench. Thanks!

 

[SCUBA King]

This one has the full schematic: Manual
What happens if you lift pins 14/15 from 4C, does it go low? If you short 2H pin 2 to gnd does it make the sound?

2h pin2 to ground, no change.
Socketing 4c now to make it easier to lift pins.

 

[SCUBA King]

P14/15 lifted on 4c. Tome as high on chip off board.

P2/3 on 2h are now floating.
No change on walk sound.

 

[SCUBA King]

This one has the full schematic: Manual
What happens if you lift pins 14/15 from 4C, does it go low? If you short 2H pin 2 to gnd does it make the sound?

Just a poke to send to the top