Gottlieb System 3 control board troubleshooting

[Miles Gentry]

I've got a System 3 DMD game that has control board issues. I've swapped the ROM for a known good ROM and connected a known good display board. When the board boots, I get a fast blink followed by a brief pause then more fast blinks. I've poked around with the logic probe looking at the levels of U11, U14, U16 comparing them to a known good control board's levels. So far, I haven't found anything out of the ordinary. Removing the battery changes results in the usual way, except the low battery/u3/u6 message is in German. R5 and R6 are in spec, C11 and C21 are out (2uF) but not as far out as my other boards that are working (6uF)

I'm about to order some components, any advice on what to look at next is appreciated.

[t***@gmail.com]

Post by Miles Gentry
I've got a System 3 DMD game that has control board issues. I've swapped the ROM for a known good ROM and connected a known good display board. When the board boots, I get a fast blink followed by a brief pause then more fast blinks. I've poked around with the logic probe looking at the levels of U11, U14, U16 comparing them to a known good control board's levels. So far, I haven't found anything out of the ordinary. Removing the battery changes results in the usual way, except the low battery/u3/u6 message is in German. R5 and R6 are in spec, C11 and C21 are out (2uF) but not as far out as my other boards that are working (6uF)
I'm about to order some components, any advice on what to look at next is appreciated.

Which values do you have in R5 and R6? Ideally they should be 680k. If yours is an early machine they might be 330k. You say C11 assuming you mean C20 and not sure what you mean by saying they are "out". They are 20% 1uf caps but the ESR is what matters more especially if you are measuring in circuit.

After you pulled the battery and booted did you try pressing the reset button on the MPU board and see if it booted correctly at that point? Since you get a low battery message that's a good sign and perhaps your only issue is the battery.

viperrwk

[Miles Gentry]

Post by t***@gmail.com

Post by Miles Gentry
I've got a System 3 DMD game that has control board issues. I've swapped the ROM for a known good ROM and connected a known good display board. When the board boots, I get a fast blink followed by a brief pause then more fast blinks. I've poked around with the logic probe looking at the levels of U11, U14, U16 comparing them to a known good control board's levels. So far, I haven't found anything out of the ordinary. Removing the battery changes results in the usual way, except the low battery/u3/u6 message is in German. R5 and R6 are in spec, C11 and C21 are out (2uF) but not as far out as my other boards that are working (6uF)
I'm about to order some components, any advice on what to look at next is appreciated.

Which values do you have in R5 and R6? Ideally they should be 680k. If yours is an early machine they might be 330k. You say C11 assuming you mean C20 and not sure what you mean by saying they are "out". They are 20% 1uf caps but the ESR is what matters more especially if you are measuring in circuit.
After you pulled the battery and booted did you try pressing the reset button on the MPU board and see if it booted correctly at that point? Since you get a low battery message that's a good sign and perhaps your only issue is the battery.
viperrwk

This board has 330k resistors, I'll check the ESR when I get home. I wasn't too surprised by the capacitance measuring at 2uF in circuit, I've seen .7uF to 6uF on other System 3 control boards. Pulling the battery and pressing reset results in the same LED flashing. I'm reasonably certain the Dallas 1210 is behaving correctly.

[t***@gmail.com]

Which game and ROMs have you had the problem with? Since it has 330k resistors I assume it is an early game or had the CPU board swapped in from another early game. Might also be able to fix it with a ROM update as well depending upon the game though since it has the 330k resistors I'd swap those out first regardless.

viperrwk

[Miles Gentry]

Post by t***@gmail.com
Which game and ROMs have you had the problem with? Since it has 330k resistors I assume it is an early game or had the CPU board swapped in from another early game. Might also be able to fix it with a ROM update as well depending upon the game though since it has the 330k resistors I'd swap those out first regardless.
viperrwk

This is using the SFIIv1 ROM, I've got a SFIIv3 ROM as well, but nothing earlier in my current pile.

[Miles Gentry]

Post by Miles Gentry

Post by t***@gmail.com
Which game and ROMs have you had the problem with? Since it has 330k resistors I assume it is an early game or had the CPU board swapped in from another early game. Might also be able to fix it with a ROM update as well depending upon the game though since it has the 330k resistors I'd swap those out first regardless.
viperrwk

This is using the SFIIv1 ROM, I've got a SFIIv3 ROM as well, but nothing earlier in my current pile.

Is there any information on when Gottlieb transitioned to the 26285-1 revision boards? The working board is a 26285 with the 330k resistors. Its factory original w/ matching serial number/model number on the paper tag. The non-working board is a 26285-1, with no tag, I assume someone has done lots of board swapping in this game. The display board is from a Wipe Out and has the wrong DSPROM. That display board is dead anyway, the GAL is fried and I need to get one programmed. I'm using the proper SFII DSPROM in a known working display board for all of this testing.

My mistake on R5 and R6, I was operating from memory. Both R5 and R6 are the correct 680k resistors.

What kind of ESR should I be seeing on those capacitors?

I'm starting to run out of ideas on this thing. I may try a fresh U11 when I get some of those in.

[t***@gmail.com]

Post by Miles Gentry
Is there any information on when Gottlieb transitioned to the 26285-1 revision boards? The working board is a 26285 with the 330k resistors. Its factory original w/ matching serial number/model number on the paper tag. The non-working board is a 26285-1, with no tag, I assume someone has done lots of board swapping in this game. The display board is from a Wipe Out and has the wrong DSPROM. That display board is dead anyway, the GAL is fried and I need to get one programmed. I'm using the proper SFII DSPROM in a known working display board for all of this testing.
My mistake on R5 and R6, I was operating from memory. Both R5 and R6 are the correct 680k resistors.
What kind of ESR should I be seeing on those capacitors?
I'm starting to run out of ideas on this thing. I may try a fresh U11 when I get some of those in.

With CBW, R5 & R6 were 330k resistors and the game came with a 6116 at U3. By Wipeout, R5 & R6 were still the same value but U3 was a 6264. By Stargate R5 & R6 had gone to 680k with the 6264 RAM. AFAIK, the base PCB is the same between them all the only difference is what they are stuffed with.

On known good boards I get an in-circuit ESR reading on C20 and C21 of about .75 ohms.

SFII ROM update will not solve the garbage boot problem. I've tried it unsuccessfully.

Before you shotgun the board you may want to get in touch with Marco Albus for his System 3 test ROM. It checks CPU, RAM, VIAs and watchdog circuit - will help you to narrow down the problem rather than swap out something that's working.

viperrwk

[Miles Gentry]

Post by t***@gmail.com

Post by Miles Gentry
Is there any information on when Gottlieb transitioned to the 26285-1 revision boards? The working board is a 26285 with the 330k resistors. Its factory original w/ matching serial number/model number on the paper tag. The non-working board is a 26285-1, with no tag, I assume someone has done lots of board swapping in this game. The display board is from a Wipe Out and has the wrong DSPROM. That display board is dead anyway, the GAL is fried and I need to get one programmed. I'm using the proper SFII DSPROM in a known working display board for all of this testing.
My mistake on R5 and R6, I was operating from memory. Both R5 and R6 are the correct 680k resistors.
What kind of ESR should I be seeing on those capacitors?
I'm starting to run out of ideas on this thing. I may try a fresh U11 when I get some of those in.

With CBW, R5 & R6 were 330k resistors and the game came with a 6116 at U3. By Wipeout, R5 & R6 were still the same value but U3 was a 6264. By Stargate R5 & R6 had gone to 680k with the 6264 RAM. AFAIK, the base PCB is the same between them all the only difference is what they are stuffed with.
On known good boards I get an in-circuit ESR reading on C20 and C21 of about .75 ohms.
SFII ROM update will not solve the garbage boot problem. I've tried it unsuccessfully.
Before you shotgun the board you may want to get in touch with Marco Albus for his System 3 test ROM. It checks CPU, RAM, VIAs and watchdog circuit - will help you to narrow down the problem rather than swap out something that's working.
viperrwk

I'll try to track down the test ROM.

The broken board is stuffed with what I think is a 6264 (Sharp LH-5168). The working boards I have are stuffed with a Fairchild 8464A which I believe also cross references to a 6264. Looks like the board I have is later than SFII and Wipe Out, its consistent with the stuffing for a Stargate or other later boards. The ESR I'm getting is no where near .75 ohms. I'll swap those capacitors out and burn the test ROM and see what happens after that.

[Miles Gentry]

Replaced the capacitors and installed the test ROM. I get one moderately bright flash at power up then very faint (had to turn the lights out to see them) quick flashes. The quick flashes may be the SRAM being tested. I'll try to carefully pull the DS1210 off the board and jumper around it.

[t***@gmail.com]

Post by Miles Gentry
Replaced the capacitors and installed the test ROM. I get one moderately bright flash at power up then very faint (had to turn the lights out to see them) quick flashes. The quick flashes may be the SRAM being tested. I'll try to carefully pull the DS1210 off the board and jumper around it.

Do you have an LED on or are somehow monitoring address line A8? Does it flash/strobe continuously after the on-board LED turns off? If A8 is not strobing then the test hung which is indicative of a bad SRAM/battery/DS1210.

viperrwk

[Miles Gentry]

Post by t***@gmail.com

Post by Miles Gentry
Replaced the capacitors and installed the test ROM. I get one moderately bright flash at power up then very faint (had to turn the lights out to see them) quick flashes. The quick flashes may be the SRAM being tested. I'll try to carefully pull the DS1210 off the board and jumper around it.

Do you have an LED on or are somehow monitoring address line A8? Does it flash/strobe continuously after the on-board LED turns off? If A8 is not strobing then the test hung which is indicative of a bad SRAM/battery/DS1210.
viperrwk

I've got the test LED hooked to A8. I found a solder bridge on the GPROM socket. That's been removed and the test EPROM boots. I get passed the first slow flash (EPROM running, clock is ok, etc). The test LED locks on during the RAM test portion of Marco's EPROM. The DS1210 is out of the circuit and I've jumpered over its pads, per Marco's instructions. I may swap out the SRAM since that's just about the last thing left in this portion of the test EPROM.

[Miles Gentry]

Replaced the SRAM and the board passes all the tests in the test EPROM. Looks like the original battery may have leaked and took out the DS1210 and the SRAM. I put the original ROM back in and the game boots.

Thanks for the help!

[t***@gmail.com]

Post by Miles Gentry
Replaced the SRAM and the board passes all the tests in the test EPROM. Looks like the original battery may have leaked and took out the DS1210 and the SRAM. I put the original ROM back in and the game boots.
Thanks for the help!

Marco's test ROM is a great help for the Sys3 CPU. Looks like there were several issues with your board. Glad you found and corrected the problems. Thanks for reporting the result.

viperrwk

[r***@gmail.com]

Hi guys,

Can you please let me know, where i can find the test eprom from marco?
Also, i have issues with my rescue 911, as it has the 6116 board in there.
So my decision is to replace 6116 to 6264, change r5/r6 to 680k and replace c20 and c21.
Can you tell me how i need to change the jumpers and where to find the rescue 911 rom file?

Thx a million for your help.

Rgds

Rainer

[t***@gmail.com]

Post by r***@gmail.com
Hi guys,
Can you please let me know, where i can find the test eprom from marco?
Also, i have issues with my rescue 911, as it has the 6116 board in there.
So my decision is to replace 6116 to 6264, change r5/r6 to 680k and replace c20 and c21.
Can you tell me how i need to change the jumpers and where to find the rescue 911 rom file?
Thx a million for your help.
Rgds
Rainer

Email sent. I wouldn't change the 6116 until after running the test ROM to make sure everything is working correctly. To support the 6264 remove jumper J3 and install jumper at J4.

viperrwk

[c***@provide.net]

Post by t***@gmail.com

Post by r***@gmail.com
Hi guys,
Can you please let me know, where i can find the test eprom from marco?
Also, i have issues with my rescue 911, as it has the 6116 board in there.
So my decision is to replace 6116 to 6264, change r5/r6 to 680k and replace c20 and c21.
Can you tell me how i need to change the jumpers and where to find the rescue 911 rom file?
Thx a million for your help.
Rgds
Rainer

Email sent. I wouldn't change the 6116 until after running the test ROM to make sure everything is working correctly. To support the 6264 remove jumper J3 and install jumper at J4.
viperrwk

can someone please email me Marco's gottlieb sys3 test rom too?
cfh at provide.net