On a Volcano there are four 6 digit score displays, if some one was to accidentally remove the connector from the displays while it was on and it screwed up the other displays what would need to be looked at or done? So a little background a friend was having issues with two of the displays intermediately working and then would lose a digit or segment. I thought to wiggle the IDC wires maybe a bad connection and then maybe try to re-seat the connector not realizing i forgot to mention while game is off (DUH). Well the connectors were removed and reseated with game powered on and now there is Digit#2 on players 1-3 and a few segments missing on all four displays are out. I believe it to be a data problem know more than a power or connectivity issue but correct me if not. From what i read on wiki the digits and segments are controlled by logic IC.

Taken from Wiki: NOTE: Do not connect or disconnect the display connectors or connectors A1J2 and A1J3 on the MPU (right hand side) with the power on! Doing so WILL damage the MPU board display logic ICs.

Display Issue With Multiple Displays
If the problem shows up on two or more displays, suspect one of the two connectors on the CPU board (A1J2 or A1J3), one of the two connectors on the two displays (they are daisy-chained with an IDC connector), or the chips which control the display data on the CPU board. If there is a digit issue, the issue will be present on player 1 and 3 or player 2 and 4 displays. If there is a segment issue, the issue will be present on player 1 and 2 or player 3 and 4 displays, and the status display. If more than 4 scoring displays are used, on games such as Pink Panther, Black Hole, Haunted House, Devil's Dare, etc., consult the game manual for display digit and segment mapping.

The charts listed below, map out each signal to each specific display. The first chart maps the display digit information, while the second and third charts map the display segment information. This information only applies to games where 4 scoring displays and 1 status display are used, although digit group names have been added, if more displays are used. All of the charts apply to System 80 and 80A, but not 80B.
Display Digit Information
Digit Number Display(s) CPU Pin Connection Chip on CPU Board - Pin
D16 (80A only) Players 1 & 3 (Group F) A1J3-16 Z26-8
D1 Players 1 & 3 (Group D) A1J3-1 Z17-4
D2 Players 1 & 3 (Group D) A1J3-2 Z17-6
D3 Players 1 & 3 (Group D) A1J3-3 Z17-12
D4 Players 1 & 3 (Group D) A1J3-4 Z17-10
D5 Players 1 & 3 (Group D) A1J3-5 Z17-8
D6 Players 1 & 3 (Group D) A1J3-6 Z24-2
D13 (80A only) Players 2 & 4 (Group F) A1J3-13 Z26-4
D7 Players 2 & 4 (Group E) A1J3-7 Z24-4
D8 Players 2 & 4 (Group E) A1J3-8 Z24-6
D9 Players 2 & 4 (Group E) A1J3-9 Z24-12
D10 Players 2 & 4 (Group E) A1J3-10 Z24-10
D11 Players 2 & 4 (Group E) A1J3-11 Z24-8
D12 Players 2 & 4 (Group E) A1J3-12 Z26-2
D13 Status (Group F) A1J3-13 Z26-4
D14 Status (Group F) A1J3-14 Z26-6
D15 Status (Group F) A1J3-15 Z26-10
D16 Status (Group F) A1J3-16 Z26-8

So if Digit 2 is out i would want to replace the Z17-6 chip? any chance someone knows what chips they are?

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Ok thanks, waiting on a reply

Anyone?

Thank you very much i will do this and follow up.

I was thinking about putting sockets in so any future issue would be easier to swap chips but unsure if they use .3 or .6 sockets? Also if you shut off the game and a few of the segments are out what is that an indication of?

Thanks Again

I replaced the said chips now I have all digits and all segments stay lit and game plays but no score reading on displays. Any help be great

Anyone have any ideals why score isn't reading I have all the digits and segments stay lit?

No

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I replaced z19,z21,z17 and z16 someone messed it up before but think I got it right and I replaced z25

Should pins 6 and 7 be ground on chip z25 as seen above in the middle? z21 I replaced with a 74ls48 and next to it is z22 which I tested... z23 is still original 7448 and left of it is z23 I tested showed good.Tested z16-z26 got 4.4 to 6.7 as the testing stated so all those appear good per this test method http://www.pinwiki.com/wiki/index.php?title=General#Testing_an_integrated_circuit

On z25 which is the 74154 ic chip are pins 6 and 7 are ground? The above schematic shows ground symbol between 6 and 7 does that mean that both connected ground? I switched it out so making sure I did not over solder the connector. The 7400 ic on z13 and z14 tested .6 to .8, tested the two 6118 chips on each display tested good using method attached found on wiki.
Found a nice picture showing what chips are what! Could the u5 display control riot chip be my issue?

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Game still plays but without scoring, any help on what to try next would be great thanks, looking to get info asap so parts can be ordered and received by the weekend

Well, obviously there is a big mistake when replacing U16 (7404).
Indeed, we see in the photo the segments "h" (the segment "1" specific to Gottlieb displays) permanently lit.
The segments "h" are controlled directly by the RIOT U5 (6532) and transit only by Z16 (7404). So it is obvious that either the 7404 is deffective, or there is a bad weld somewhere on this socket.
And since Z16 is downstream of all 74175/7448 circuits, if it is dead, nothing else can be displayed. So that's for sure, the problem comes from the Z16 that has been changed.
On the other hand, the strobe part (Z25 - 74154 + Z17 - 7404) seem now to work since all the digits are displayed.</bloc

Thanks... So i went back a looked at Z16 that had been repaired by someone prior that obviously wasnt very good at repairs, so I removed Z16 due to globs of solder sticking out from three of the legs and a few of the globs of solder looked as if it had fallen off the back due to the pads being burned off so i thought i would socket it and try and clean up the mess. So i put a socket in and checked all continuity on all the legs to the PCB and the traces going out to make sure they wer making good contact with the socket and they are were except one that had the big glob of solder as if they were trying to give it legs, looking at it the top tracer on the board apparently had gotten pulled up and was missing a small section so looking at it the tracer went from one leg of Z16 to the bottom leg on Z18 so i put a jumper lead in on the back side as can be seen to make that continuity and checking everything was fine.

So after reading your advice i started looking and noticed the pulled up tracer on the board left a track on the board that appered to be connecting the two legs on Z16 and Z18 to resistor below Z16... Hmmmm.. So this might be my issue if you could verify that is correct...

Also i have purchased just about every chip for this board minus the U4,U5,U6 which i located so once i get this fixed if you need any chips for any system 80 projects you are working on let me know and i will mail them to you for your help.

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Thanks... So i went back a looked at Z16 that had been repaired by someone prior that obviously wasnt very good at repairs, so I removed Z16 due to globs of solder sticking out from three of the legs and a few of the globs of solder looked as if it had fallen off the back due to the pads being burned off so i thought i would socket it and try and clean up the mess. So i put a socket in and checked all continuity on all the legs to the PCB and the traces going out to make sure they wer making good contact with the socket and they are were except one that had the big glob of solder as if they were trying to give it legs, looking at it the top tracer on the board apparently had gotten pulled up and was missing a small section so looking at it the tracer went from one leg of Z16 to the bottom leg on Z18 so i put a jumper lead in on the back side as can be seen to make that continuity and checking everything was fine.

So after reading your advice i started looking and noticed the pulled up tracer on the board left a track on the board that appered to be connecting the two legs on Z16 and Z18 to resistor below Z16... Hmmmm.. So this might be my issue if you could verify that is correct... I have put in a small jumper on the back side from the Z16 leg to the resistor i hope will work.

Also i have purchased just about every chip for this board minus the U4,U5,U6 which i located so once i get this fixed if you need any chips for any system 80 projects you are working on let me know and i will mail them to you for your help.
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