Dig Dug Help

[DarrenF]

This chip is at location 4 k or L (going from memory and like eyes going bad).

If you can determine the actual location, we can look at the schematics and/or I can look at my Dig Dug PCB to see what's there.

If it's 4K, the the 4th printing of the manual says that's Atari P/N 137211-001. The old Atari supplier database that's floating around has this for that P/N:

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
137211-001 IC,SRAM,2Kx8,150ns,NMOS,Tri,24pin,Pwr-dn,Plastic MOTOROLA MCM2128P-15

However, the 1st printing of the manual shows "2148" in at 4J...(137199).

A good, hi-resolution, pics of the PCB would help match it up to the proper printings of the manual and schematics...

 

[kb0jjn]

I will post a pic by the week end. I think the chip is a ram chip. The other hot chip was a tmm2016. I see lots of activity on the z80 chips that I did not see before.

If you can determine the actual location, we can look at the schematics and/or I can look at my Dig Dug PCB to see what's there.

If it's 4K, the the 4th printing of the manual says that's Atari P/N 137211-001. The old Atari supplier database that's floating around has this for that P/N:

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
137211-001 IC,SRAM,2Kx8,150ns,NMOS,Tri,24pin,Pwr-dn,Plastic MOTOROLA MCM2128P-15

However, the 1st printing of the manual shows "2148" in at 4J...(137199).

A good, hi-resolution, pics of the PCB would help match it up to the proper printings of the manual and schematics...

 

[kb0jjn]

The correct location is 4j. There is another of these chips at location 3g. Here is a pic of the over all board and then the empty slot with ram chip pulled out

The biggest problem with this board was bad chips. The ram chip was bad, the z80s were bad or wrong type, and the tmm2016 @9n was bad.

Before the z80 chips had little going on most were stuck high or watch dog. Now there is lots of activity on the z80 chips.

 

[DarrenF]

You have the older of the two types of Dig Dug PCB. Refer to printings 1, 2 or 3 of the manual and/or schematics. (Printing 4 is for the newer type PCB).

4J is a 2148. Avail from arcadechips, Bob Robert, Twisty Wrist and probably other places as well.

I think that RAM is a video line buffer... not even addressable by the CPU. I can't imagine it would keep the thing from booting; but it could sure botch up your gfx.

 

[kb0jjn]

I bought this board to pull parts off of it. I never intended to fix this thing, just get the parts I needed to fix the galaga boards I have.

The more I look at this thing the less I understand about this board.

It wants 36 volts ac for audio or something like that (on pin 3) and I see no audio amp on this board.

The audio output is next to nothing when I should be hearing audio.

Half of the roms are active at any one time?

This thing is just moking me and pissing me off to no end. That makes me want to fix it even more.

I am sure there is another board to this pcb. and it probably has the audio amp and such. The schematics shows 2k and 3k. The chips there only need about 5 volts.

My question is where is the audio amp for this board as I don't see it here like on the Galaga, Karate Champ, Elevator Action, Heavy Barrel and many other games.

 

[DarrenF]

Dig Dug, while it was developed by Namco, had its PCB "Atari-izied." Thus, while it is similar to Galaga in general electronic design, its phyiscal layout and cabinet wiring harness were similar to other Atari games of the era.

Thus, the game PCB generates unamplified audio, which was amplified by an A/R-II board on the original. You should be able to run it through an amplified PC speaker if you don't have an A/R-II handy.

However, the 36 VAC going to the PCB wasn't very common, even for Atari boards. It has nothing to do with audio. That is only used by the EEPROM that saves the high scores. (If you care, it is used to derive -29VDC, which is then used to program the ER2055). The ER2055 was only used by Atari on about half a dozen or so games.

These answers, and many more, are easily available to anyone who bothers to look at the wiring diagrams and schematics...

 

[kb0jjn]

I will look over the diagrams and schematics, I just could not figure why the pcb wanted the 36vac when there was no audio amp.
I am learning more about the cabs and monitors. I tend to stay on the pcb repair part of the threads. They are easier for me and don't take much room to store.
Thak you for the details on the 36 volts ac that part made little sense to me, without the audio amp.

Dig Dug, while it was developed by Namco, had its PCB "Atari-izied." Thus, while it is similar to Galaga in general electronic design, its phyiscal layout and cabinet wiring harness were similar to other Atari games of the era.

Thus, the game PCB generates unamplified audio, which was amplified by an A/R-II board on the original. You should be able to run it through an amplified PC speaker if you don't have an A/R-II handy.

However, the 36 VAC going to the PCB wasn't very common, even for Atari boards. It has nothing to do with audio. That is only used by the EEPROM that saves the high scores. (If you care, it is used to derive -29VDC, which is then used to program the ER2055). The ER2055 was only used by Atari on about half a dozen or so games.

These answers, and many more, are easily available to anyone who bothers to look at the wiring diagrams and schematics...

 

[khite]

Ok guys, I just replaced the edge connector. Now I am getting a few mV coming from the ARII board. R4 had some burn marks on it so I replaced it. When I turn the machine on that resistor gets extremely hot. Would that be a sign of Q2 needing replaced.

Thanks

 

[kb0jjn]

Ok guys, I just replaced the edge connector. Now I am getting a few mV coming from the ARII board. R4 had some burn marks on it so I replaced it. When I turn the machine on that resistor gets extremely hot. Would that be a sign of Q2 needing replaced.

Thanks

here is how to test a transistor but there are vids on u-tube also...this is just a description of how to do a test.

http://www.electronics-radio.com/articles/test-methods/meters/multimeter-diode-transistor-test.php