DE Display problem - ALL ON ?

[Marty Machine]

Hi All,

I just bought another pin home today "Time Machine" from DE.
Game works a treat, been playing it most of today/tonight.

Problem: the score display isn't working, in fact there are 2 alphanumeric (7digit) displays, and 2x 7seg (7digit) displays underneath them.
The number on the Display PCB (under the DE logo) is 520-5014-00, in case someone has a schematic or can refer me to the appropriate MCU card for further info.

- The Alpha numberic displays have EVERY segment and comma turned ON.
- The 7-seg displays are simply OFF.

I did the basics, replugging all the connectors on the display pcb, and the ribbon cable between display and MCU board, plus 'crunching' in a few socketed IC's in the MCU card too.

No change as yet.

If i remove the ribbon cable, the display is totally OFF.....so i'm assuming the ribbon carries data & strobes?
Due to the ribbon having this effect, i now feel the data/strobe driver(s) on the MCU might be dead or suss? or at least a supply for them has gone, who knows at this early stage....

I'm in no urgent hurry to get into fixing this, as i'm having a ball playing the pin regardless 
Not having a 'Time Machine' manual, or at least the display/mcu card isn't helping either 

Maybe someone has seen this same DE sympton, and will tell me it's C38 or D17 as usual hehehehe.

Thanx in advance,
MM.

[MartyJ]

Its got to be the Flux-Capacitor.  Unless its reading 1.21 gigawatts it won't work......   

Sorry, watched the movie the last two weekends?

The setup on the D.E's re displays...Is that the same as a System 11b.  Seems almost identical to the issue I was having with mine...


http://aussiepinball.com/index.php?topic=342.0

I still need to replace 1 x UDN7180 to fix a segment.

[MartyJ]

Its got to be the Flux-Capacitor.  Unless its reading 1.21 gigawatts it won't work......   

Sorry, watched the movie the last two weekends?

The setup on the D.E's re displays...Is that the same as a System 11b.  Seems almost identical to the issue I was having with mine...


http://aussiepinball.com/index.php?topic=342.0

I still need to replace 1 x UDN7180 to fix a segment.  Cross your fingers its not those as they are near on impossible to find!  Although, I would swap my 95% working display for an F14!

[Retropin]

Pinballfixers site has DE schematics on it - can download from there

[Pinball Fixers]

Here's the link to the Data East Schematics...

www.pinball-fixers.com/data-east-pinball-schematics.html

You need the "Combined Display Schematic".

[Marty Machine]

Thanx guys, i just D/L'd some DE ccts form owens site....

should be a good start, trying to locate which board the flux capacitor is on 

MM.

[Pinball Fixers]

Thanx guys, i just D/L'd some DE ccts form owens site....

should be a good start, trying to locate which board the flux capacitor is on 

MM.

It's in the Delorean, under the playfield... or is it behind the backglass??? Hmmm, can't remember now...

[MartyJ]

Hey MM,

I noticed a few service bulletins in relation to your machine on here.  I'm sure you are all ready aware but here tis:

http://www.sternpinball.com/servicebulletins.shtml

[pinnies4me]

It's in the Delorean

Oh no, not the De Lorean!

[Marty Machine]

Hi All,

Out of sheer boredom today i decided to look deeper into my display problem.

Looking at the schematic pointed me to a 6821 (PIA) chip that controls the data & strobes to the score display PCB.
The 6821 was in a socket, and the other 6821's on the main board were not, immediately i was suspect of the socketed PIA.
I replaced the 6821 today, and after powering up the pin, i can now see Alpha-numeric words & scoring.
I've played thru many games and everything displays as expected.....so far so good.

However, that's only the 'top' 2 displays (being the 2 Alpha-numeric ones) that work nicely.
The 2 displays under them (7-seg) are still just OFF, nothing at all, ever!

I'll spend more time next week on this, as i need to dig out my logic probe and/or Cro to trace the missing signals that drive the 7-seg displays.
I'm guessing (at this stage) that a buffer chip on the display PCB has paffed out, soon to be confirmed! 

I play the machine too much to be bothered getting Techy with it, at the moment 

Getting there ... 
MM.

[Strangeways]

Good stuff Marty... Just enjoy it for a while - I had a feeling you were right when we spoke about this at Mark's.

[Marty Machine]

Thanx Nino, yep, i'm always right hahahahahahaha.

Damn hard to fix machines when playing them all the time. 

I go back to work next week, so i'm about to start taking my boards in, and replace all connectors and IC sockets as a preventive measure for future problems, then onto de-soldering various chips too. 

MM.

[Nug]

Its got to be the Flux-Capacitor.  Unless its reading 1.21 gigawatts it won't work......   

Sorry, watched the movie the last two weekends?

The setup on the D.E's re displays...Is that the same as a System 11b.  Seems almost identical to the issue I was having with mine...


http://aussiepinball.com/index.php?topic=342.0

I still need to replace 1 x UDN7180 to fix a segment.

i maybe wrong but i thought sys11a has the half and half ? b's are all +10million score ability releases?

display data needs to be checked with logic probe.  cpu side? i doubt youd get past startup...the pia will flag fault.

most likely logic on display pcb.