ttbit
New member
- Joined
- Nov 23, 2012
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Hello All,
I am new to the forum and glad to see something like this out here. I have been out of the loop for awhile on the "arcade front" and my son and I decided to tackle fixing our Tron machine. Some years ago I decided to clean the connections, as we had some intermittent issues and then we ended up moving in the middle of me having the thing apart. It had a lot of downtime between moves. I had no screen and no sound so I decided to leave it be for awhile.
Flash-forward to current time and I found that I had the monitor connector on the wrong set of pins. I also found that I had one of the ribbon cables misaligned (off by one pin on one side). Geeez. I usually pay pretty good attention to detail also. Maybe it helped that I have glasses now.
Here is what I have found:
- Cables plugged in correctly - Now get D4 Error
- Reseated all chips in sockets - D4 Error
- Ribbon cables have some bad connections checking over 4 ohms. Replaced. D4 error
- Found rom D4 had one error in it. Burned a new rom. D4 Error.
- Copied the old rom to a Mame install and was able to reproduce error, so I know the rom was bad.
- Had some Hitachi hn482764g-3 chips laying around so burned D1-D5 images to these and replaced. D4 Error
I purchased a Genius G540 to check and burn chips. What I have found is that this device will not read all of my 2764s correctly. If you read the chips in, a different checksum will show intermittently. Either the chips are weak, or this thing is going too fast, as these are -4 chips and it seems to do fine with -3. Erasing and burning the same chips do not work. It bombed on my d1 chip and now I am thinking that chip was probably fine and now I have an original part not usable. At first I thought almost all of my roms were bad. It took me awhile to find out that it was reading improperly.
Oh and get this....the one chip that reads the same EVERY time in my burner is the D4 chip!
What are the odds? Actually the last two of the set check fine also, so I did not burn those.
I am amazed that everything I did produced the D4 error. I would be happy to see something different. Maybe I will yank the d2 out and see if I get a d2,d4 error.
5v supply checked consistent over all caps on the rom board. If anything, slightly high. I am using an older good Fluke Meter for these checks.
Any suggestions? I have not tried to print out the schematic yet. Reading it in the pdf was a little tough to follow. I thought I would bounce this here and see if someone else has run into this.
Thank you,
Don
I am new to the forum and glad to see something like this out here. I have been out of the loop for awhile on the "arcade front" and my son and I decided to tackle fixing our Tron machine. Some years ago I decided to clean the connections, as we had some intermittent issues and then we ended up moving in the middle of me having the thing apart. It had a lot of downtime between moves. I had no screen and no sound so I decided to leave it be for awhile.
Flash-forward to current time and I found that I had the monitor connector on the wrong set of pins. I also found that I had one of the ribbon cables misaligned (off by one pin on one side). Geeez. I usually pay pretty good attention to detail also. Maybe it helped that I have glasses now.
Here is what I have found:
- Cables plugged in correctly - Now get D4 Error
- Reseated all chips in sockets - D4 Error
- Ribbon cables have some bad connections checking over 4 ohms. Replaced. D4 error
- Found rom D4 had one error in it. Burned a new rom. D4 Error.
- Copied the old rom to a Mame install and was able to reproduce error, so I know the rom was bad.
- Had some Hitachi hn482764g-3 chips laying around so burned D1-D5 images to these and replaced. D4 Error
I purchased a Genius G540 to check and burn chips. What I have found is that this device will not read all of my 2764s correctly. If you read the chips in, a different checksum will show intermittently. Either the chips are weak, or this thing is going too fast, as these are -4 chips and it seems to do fine with -3. Erasing and burning the same chips do not work. It bombed on my d1 chip and now I am thinking that chip was probably fine and now I have an original part not usable. At first I thought almost all of my roms were bad. It took me awhile to find out that it was reading improperly.
Oh and get this....the one chip that reads the same EVERY time in my burner is the D4 chip!
I am amazed that everything I did produced the D4 error. I would be happy to see something different. Maybe I will yank the d2 out and see if I get a d2,d4 error.
5v supply checked consistent over all caps on the rom board. If anything, slightly high. I am using an older good Fluke Meter for these checks.
Any suggestions? I have not tried to print out the schematic yet. Reading it in the pdf was a little tough to follow. I thought I would bounce this here and see if someone else has run into this.
Thank you,
Don