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Frankensteinowner

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  1. I removed the BAT diode, jacked the 5V close to TTL levels, getting close to 3.3V on rail but all to no avail. As other users suggested - tried increasing the values of the cap on the reset circuit but, again, not cigar. Guess it may be down to the CPU itself and I've no intention of trying to remove it - even my soldering isn't that good. Will just have to knock up a relay circuit to press the button a brief while after power up - that is on hold until I get my display card working - have removed all 3 PLDs - just waiting for the programmer to arrive. If that doesn't work, the 68B45 is next on the hit list.
  2. I tried Lucky's suggestion - nothing shown on the DMD - I put a scope on the lines to the display - only a couple of them have signals on immediately after a reset (when I'd expect to the display to show the rom version) - it looks like the controller card is defective. Has anyone used the pinballSP controller with the PIN2DMD? (I see they sell their own version but, I'd rather not spend another 300 euros on one if I don't need to.
  3. Many thanks - I see the ROM images are on that link too 🙂 I'll also hunt down a test rom - I see there is something called Leon - if the display card / display work, I'll head down that route Thanks again Lucky - I have some more avenues to try now
  4. Many thanks lucky - you're a top man - just to be clear - if I ground pin 20 of the incoming data cable, it should display the rom version? The controller was resetting but, that turned out to be a corroded pin on the data cable connector - cleaned that and it stopped resetting. I'll give your suggestion a go - if I can confirm the controller is working, I'll prob make a new ribbon cable - if that doesn't fix it, just buy a new Rottendog CPU. I'll fix the 4.6V - the PSU is running at 4.99V so, the voltage drop must be in the cables. Once again Lucky, many thanks for your help.
  5. Thanks Lucky - I jumped 5V in from a bench supply (as the 5V was running at about 4.6V) -looking at the 68000 data bus with a scope, its in a tight loop - probably waiting for data from the game processor. Should the PIN2DMD operate OK with the 5V rail at 4.06V? I soooo can't get to the bottom of this - I contacted someone who fixes machines for a living but, he said he wasn't taking on new customers.
  6. I have a 192x64 PIN2DMD on a MSF - was working fantastically but, now it won't display anything from the machine - just the boot screens. I looked at the input test screens on the display - its showing 'Pin 9 close', even with the input ribbon cable removed. The resistor and capacitor check out OK. Is this right or has my board got a fault? All of the other inputs only show close when I ground the appropriate pins. Looking at the circuit, pin 9 goes into a '123 which I assume is to either stretch or condition the pulse. The input to this device (from Pin 9) seems to be stuck at about 1v. The supply voltage (Vcc) is about 4.1V (which I think is needed to keep the display modules happy). Looking on a scope, shorting pin 9 to gnd doesn't seem to trigger the '123 The game has started acting very strangely - does the game processor get any feedback from the display (which if playing up could explain the problem) or is it a 'write only' device? As ever, any help much appreciated - I really want to get my game back up and running!
  7. Thanks guys Can one of you confirm what voltage you're getting out of the switching regulator - I understand the R32 change was to drop this but, what should I be seeing here? The BAT60 appears to be in series with the output of the 3V3 regulator - Lucky - do you recall if this was to deliberately drop the 3V3 or is there another reason for it? I'll look up what the dropout voltage is on the regulator too - if I've only got about 4V going in, the regulator may be dropping out. Sounds like Lucky has a much higher voltage at the regulator output than I have. If one of you guys can tell me what the 5V should be, I may adjust the R32 to see if raising this brings up the voltages and hopefully, the unit will reset properly (if not, I'll just build a little astable to hit the reset button a second after the power comes up. And my modules are different colours - is this what I need: https://www.ebay.co.uk/itm/LED-SIGN-P2-5-PH2-5-64-64-Pixels-Dot-RGB-Full-Color-LED-Module-Board/402638418786 Is £28 each a fair price? Thanks both for your help so far.
  8. Sorry - my mistake - was R32 - looks like it sets the output voltage on switching regulator. @Lucky1 - are you able to provide any info on what the limits of the 3V3 rail should be - mine does seem very low at 2.66V - maybe this is why the board doesn't start correctly? (it runs fine once reset - I'm very pleased with it). Peter
  9. I took the board into the office today and connected it to a bench supply set to 18V - observed the reset line on a scope - waveform was as expected though the device didn't restart. Pressing the reset button restarted the display correctly. I removed C2 and measured it as 111nF and fitted another 100n - the unit still wouldn't restart automatically on power-up. I fitted a 1uf and the rise time was extended as expected however, the device didn't reset without manual intervention. I did measure the voltage of the 3V3. It looks as if R23 has been manually replaced on the board with a 4K7 (the board is marked as 3K9) - the supply voltage was 2.66V @Lucky - Is this as expected or should it be pretty close to 3V3? I measured the 5V at the red and black cables that go to the display modules - these were just over 4V. I tried fitting a 3k9 this raised the 3v3 to about 3V however, the board still wouldn't self start so, I returned the resistor the 4k7 where there line returned to 2.73V but, it still won't restart. Peter
  10. Thanks Terranigma - I'll be going into the office on Friday to change the cap - I'll put a 1uf in its place to hold the reset low wile the supply comes up.
  11. Thanks as ever Lucky - no suggestion its a design issue - I'll stick scope on the reset line and check the rise of the reset line - I have SMD soldering at work so happy to whip the 0.1's off as needed. I'll update when I've worked out what the issue is. Thanks for everyones help
  12. How do I tell if it was made by PCBway? I've had a look at the circuit diagram - its the traditional way of controlling the reset line and as per the datasheet. What was the solution on the cards you had? Reset controllers are cheap and easy to use but, would be nice to try and get it to work without - bigger capacitor to hold the reset line low until the supply comes up? Happy to help try and get to the bottom of this.
  13. Thanks Lucky - I'll take a look - think I've used a MAX707 in the past - they cost hardly anything on Ebay
  14. I've got a 192x64 Evo installed in a Frankenstein - when I previously posted that it wouldn't self reset on power up, Lucky suggested a power supply issue as I was trying to use the machines 18V power supply (though looking at it, this comes from quite a substantial supply in the Data East machine (its an 8A fuse and a massive electrolytic). As Lucky suggested, I fitted a separate supply (a 4A, 12V switch-mode) that is controlled from the machines main power switch. Unfortunately, the display still doesn't come on when the machine is powered up - pressing the reset button brings it all to life and once on, the display is excellent - I'm really pleased with it - excellent work Lucky. Any suggestions on what else to try - Is there a circuit diagram for the Evo - I am happy to fit an external reset control IC as I've used in many of my own processor designs. As ever, all help much appreciated Peter
  15. Many thanks Lucky - I'll take a look but, my display doesn't look like that - it looks very good - nice and clear so, I'll shorten some cables (the ribbon cable is massive) and see how I get on with the booting.
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