Edmonton, AB
There is no master display board, so since this issue affects all 4 displays, it must be originating on another board. I'm not sure if its the MPU or another one.
They are 7 segment displays on a stern viper
(Topic ID: 80364)
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Viper
Stern Electronics, 1981
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Chicago Burbs, IL
Not 100% sure, but I believe this game was designed with 6-digit displays. I've read about converting the displays.
http://pinside.com/pinball/forum/topic/is-it-possible-to-convert-a-6-digit-display-to-7-digit
I wonder if your game was partially converted.
faz
I was looking at the photos on IPDB and I only counted six....My bally Star Trek was in 79...it definitely has 6 digit displays. Did you try running the machine through test mode?
So it does.... Sorry. I scanned through the manual but I saw a bunch of "999999" entries. Missed that.
faz
Maybe it's related, but when you boot the machine up, it displays a weird number in the balls played field. It sometimes shows 77 or 87
If you have all Bally displays in the game, you'll need to add a jumper.
Otherwise, look for the digit 7 strobe.
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Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info
I made a video to demonstrate the issue.
I've swapped out U9, U10, and U11, and still have the same issue.
Try unplugging them all but one and see if the problem is still there, one display might be affecting all the others displays. I would check for cracked pins on the circuit boards, And check connector pins on MPU J1
Did you try the displays in test mode?. by pressing the self test button x3 i think. My quicksilver shows all digits on all displays counting up after the third press of test button
Can you please verify that you have Stern displays in the game?
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Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The Place to go for Pinball Repair Info
Oops, didnt know there was two posts. Do what chris said and this copy paste from the other....
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So you are missing the millions digit on all displays. The digit enable signal goes from the pia, through a resistor with a cap connected to it, then out the MPU j1 connector to the displays. To troubleshoot, place the game in display test. Put your DMM or logic probe on MPU J1 Pin 7 which i think is the millions digit enable signal. Compare reading to pin J1 p1-6. They should all show similar reading in display t est. If that pin is floating or stuck high/low, check the header pin solder joint and associated PIA socket pin.
I am working off of a Bally MPU schematic. I THINK!!! Stern drives digits the million digit the same way. I am at work and only have Bally schem in front of me....
chalk up one on the big board for the CH!
Nope, that's not it. All that did was make my p4 display mirror my credit/ball display.
Still only 6 digits showing on the other 3.
Quoted from Tridentphoto:Nope, that's not it. All that did was make my p4 display mirror my credit/ball display.
Still only 6 digits showing on the other 3.
Are you sure you jumpered the right pins, counting from pin 1 on the correct side?
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Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info
So, I swapped the MPU in my EBD into the viper, I had the same issue with the displays and millions digit. Then I put the display from my EBD in the viper, and still the same issue. So I put the viper display in my EBD, and the million digit works fine. So it's not the display, and not the MPU. But there isn't a master display board, so does it run through the other boards somehow? WTF?!?
Jeff
Post a pic of the jumper you installed between pins 11 and 12 on each display please.
The description you just gave is exactly what would happen if you put a Bally display in a Stern game (millions digit won't work) and then in a Bally game (millions display works).
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Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info
On each display? Oh, that's where I messed up in the jumper issue. I put it between 11-12 on the J1 MPU plug.
I'll do this now.
Quoted from Tridentphoto:On each display? Oh, that's where I messed up in the jumper issue. I put it between 11-12 on the J1 MPU plug.
I'll do this now.
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Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info
Awesome. I suppose I should put a picture in the Wiki...
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Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info
4 weeks later
but there is something else wrong. you shouldn't have to jumper each display. Were the displays replaced from stern to bally and this is why they weren't functioning?
1 week later
Quoted from PinballDame:but there is something else wrong. you shouldn't have to jumper each display. Were the displays replaced from stern to bally and this is why they weren't functioning?
Yes...they were all Bally displays in a Stern game.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The new place for pinball repair info
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