craigmack
Member
The online manual at IPDB is horrible, but from what I can tell it looks like you are missing the wiring harness that would connect the DMD to logic power. You should have a ribbon cable for data and then one multi-colored connector for power.
The power cable probably left with the power board when they took it out of your game.
FROM: http://www.pinrepair.com/de/index3.htm#dots
On the super-size 192x64 DMD, the input voltages are low (+5 volts and +12/18 volts coming into the display). Sega did this because the 192x64 DMD has it's own power supply on the dot matrix controller board itself (the higher voltages are not supplied by the main power supply). This is unlike the other two smaller dot matrix displays.
Large 192x64 DMD power supply connector CN5. No high voltage feed to this board. The HV is generated on the dot display board itself.
* CN5 pin 1: ground
* CN5 pin 2: ground
* CN5 pin 3: ground
* CN5 pin 4: +5 volts
* CN5 pin 5: +5 volts
* CN5 pin 6: +5 volts
* CN5 pin 7: key
* CN5 pin 8: +5 volts
Cherry Super-Size 192x64 DMD, connector P3:
* NOT INSTALLED.
Cherry (only) component P2 voltages. These are converted on the board to the +80, -90 and -100 volts DC needed for the display.
o P2 pin 1,2: +12 dc
o P2 pin 4,5: Ground
o P2 pin 6: +5 dc
Booting the Large DMD on the Bench.
The cool thing about the large DMD is how easy it is to boot on the work bench. Because the large DMD generates the high voltage right on the DMD board itself, it only needs 5 and 12 volts DC to boot. (Even though it says it needs 24 volts DC as an input voltage, these displays work fine with 12 volts DC instead.) Using a standard computer power supply, the 4pin hard drive connector can be plugged directly into the large DMD power connector! Using the same computer power supply, you can power a DE CPU board and DMD controller board with 5 volts. So with just a computer power supply, you can get a DE game (CPU board, DMD controller, large DMD display) up and running in attract mode right on the work bench.
Large DMD EPROM Speed.
Also be aware the large dot matrix display requires 120 nanosecond EPROMs or faster. If using 150 ns EPROMs (which are OK in the older 128x32 and earlier displays), the super size display will not work! The 68000 processor for the display is running at 12 mHz, so the 150 ns EPROMs are too slow.
If the Super Size DMD Still Doesn't Work...
Additionally, the +5/+12 volt bridge rectifier (DB1) on the power supply board may need to be replaced. If this bridge becomes "leaky" (less efficient), it may not be able to supply the robust +5 volts needed on the display board. So if the above modification does not work, replace bridge DB1 next. When replacing DB1 on the power supply board, also solder an 18 gauge wire from the "+" lead of bridge DB1 to the "+" lead of capacitor C4. Solder another 18 gauge wire from the "-" lead of the bridge DB1 (the lead diagonal to the bridge's "+" lead) to the "-" lead of capacitor C1. Do this on the solder side of the power supply board. These added wires will help prevent future cracked solder joints on the power supply board.
Remember there is also a BR3 bridge rectifier and a fuse mounted to the backbox metal ground plane. These provide voltage to the super sized score display. Sometimes this bridge can short or the lug connectors fail. Be sure to check that.
Still doesn't work? Make sure the backbox grounding strap is tight and making good contact to the 192x64 dot matrix controller board. A loose grounding strap can contribute to super size DMD problems.
Last resort for 192x64 displays that are on again, off again, random dots, fading in and out, and rebooting. Stern suggests pulling and reseating the chips on the display board behind the DMD glass. The chips (three of them) may come out hard and may sound "gritty" on the way out and back in. But give it try.
Good Luck!!
The power cable probably left with the power board when they took it out of your game.
FROM: http://www.pinrepair.com/de/index3.htm#dots
On the super-size 192x64 DMD, the input voltages are low (+5 volts and +12/18 volts coming into the display). Sega did this because the 192x64 DMD has it's own power supply on the dot matrix controller board itself (the higher voltages are not supplied by the main power supply). This is unlike the other two smaller dot matrix displays.
Large 192x64 DMD power supply connector CN5. No high voltage feed to this board. The HV is generated on the dot display board itself.
* CN5 pin 1: ground
* CN5 pin 2: ground
* CN5 pin 3: ground
* CN5 pin 4: +5 volts
* CN5 pin 5: +5 volts
* CN5 pin 6: +5 volts
* CN5 pin 7: key
* CN5 pin 8: +5 volts
Cherry Super-Size 192x64 DMD, connector P3:
* NOT INSTALLED.
Cherry (only) component P2 voltages. These are converted on the board to the +80, -90 and -100 volts DC needed for the display.
o P2 pin 1,2: +12 dc
o P2 pin 4,5: Ground
o P2 pin 6: +5 dc
Booting the Large DMD on the Bench.
The cool thing about the large DMD is how easy it is to boot on the work bench. Because the large DMD generates the high voltage right on the DMD board itself, it only needs 5 and 12 volts DC to boot. (Even though it says it needs 24 volts DC as an input voltage, these displays work fine with 12 volts DC instead.) Using a standard computer power supply, the 4pin hard drive connector can be plugged directly into the large DMD power connector! Using the same computer power supply, you can power a DE CPU board and DMD controller board with 5 volts. So with just a computer power supply, you can get a DE game (CPU board, DMD controller, large DMD display) up and running in attract mode right on the work bench.
Large DMD EPROM Speed.
Also be aware the large dot matrix display requires 120 nanosecond EPROMs or faster. If using 150 ns EPROMs (which are OK in the older 128x32 and earlier displays), the super size display will not work! The 68000 processor for the display is running at 12 mHz, so the 150 ns EPROMs are too slow.
If the Super Size DMD Still Doesn't Work...
Additionally, the +5/+12 volt bridge rectifier (DB1) on the power supply board may need to be replaced. If this bridge becomes "leaky" (less efficient), it may not be able to supply the robust +5 volts needed on the display board. So if the above modification does not work, replace bridge DB1 next. When replacing DB1 on the power supply board, also solder an 18 gauge wire from the "+" lead of bridge DB1 to the "+" lead of capacitor C4. Solder another 18 gauge wire from the "-" lead of the bridge DB1 (the lead diagonal to the bridge's "+" lead) to the "-" lead of capacitor C1. Do this on the solder side of the power supply board. These added wires will help prevent future cracked solder joints on the power supply board.
Remember there is also a BR3 bridge rectifier and a fuse mounted to the backbox metal ground plane. These provide voltage to the super sized score display. Sometimes this bridge can short or the lug connectors fail. Be sure to check that.
Still doesn't work? Make sure the backbox grounding strap is tight and making good contact to the 192x64 dot matrix controller board. A loose grounding strap can contribute to super size DMD problems.
Last resort for 192x64 displays that are on again, off again, random dots, fading in and out, and rebooting. Stern suggests pulling and reseating the chips on the display board behind the DMD glass. The chips (three of them) may come out hard and may sound "gritty" on the way out and back in. But give it try.
Good Luck!!
