Hi everyone,

I have a Williams Fire! barnfind that needs some servicing.
The machine was in a bad shape and there was not much working.
After some diagnostics and repairs, i got it to work somehow.

Latest problem:
- There was no speech sound:
I have written new roms for game/sound/music.
The speech was back on and the sound also. With the original sound roms, there is no speech

BUT, after a short time i get message: "memory protect fail"
The MCU board fails somehow and the 5V LED blinks, like the MPU does not boot.
I have removed the U21 and U22 and the MPU looks stable.

WHEN i press the diagnostic switch on the MPU, i get 2 flashes from the diagnostic LED and 8 from the blanking LED.
On display i see alternation U10 PIA fail and memory protect error.

I doubt that the U25 ram might be bad, because it keeps its data. For example, i add a credit, shut down the machine and restart, the credit is still on.

Should i replace the PIA U10?

Another question:

The ROM chips are GI manufactory.
I have a eprom programmer, a TL866II+ but i can't find that manufacturer in the list. I get ID error from the eprom. When i disable ID-check, i can read the data on the eprom.
I have used ST M27C256 for replacement. So, i wonder if those are fine.

Thanks for the help and tips.
IMG_20240408_094229 (resized).jpgIMG_20240408_094621 (resized).jpgIMG_20240408_094626 (resized).jpgIMG_20240406_152243 (resized).jpg

Reading some other topics about a Williams pinball concerning the same MPU:

Should i change W2 to W3?

W2-W3 (resized).PNG

PinRetail

Thank you, i might look into that.

But a more weird (or not weird) question is, i have used 27C256 roms for all of them, i just duplicated the rom of U26 to fill the eprom.
It says that for (forgot where i have seen that) SW2 should be set for eproms 27c512 and to SW3 for 27c256 eproms.
My board is set for 27c512 while it has 27c256 installed.
So, should i change this jumper to W3?

W7 has also been cut, but i can reset that to english default again.

Thanks

I have replaced the U10 PIA with a ST version instead of a Motorola.
The problem seems to be gone.
Pressing the diag switch on the MPU shows no errors.

What i still not have, or sometimes i do is, there is no speech.
I have changed U26 U27 but still the same.
Sometimes, i did hear some speech, not always, but that was before i have changed the U10.

I have downloaded the BIN files from IPDB and compared the content with the original rom and it matched.

Changing L2 with L3 version of the game rom does not make any difference.

Bad contact?
I might change the IC sockets for those also perhaps.

Sound is OK and gameplay is OK, only bell and knocker seems not to be working, i might check that later.

Tuukka

Should i go for this axial version
https://www.mouser.be/ProductDetail/Vishay-Sprague/53D183G025JT6?qs=sGAEpiMZZMsh%252B1woXyUXj6eHMXVUjUVm5rnZrwfbhMM%3D

or for this radial design and lengten the legs. This last is much cheaper
https://www.mouser.be/ProductDetail/EPCOS-TDK/B41231A5189M000?qs=sGAEpiMZZMsh%252B1woXyUXjziWAS1Gcgm5KYf79DdCGNg%3D

Measurement at the 5V rail shows 4.85v

I have ordered a 6116 NVRAM

Maybe this can solve most of the problems.

I had again the memory error :/

SRAM U25 tests good, also U23 sound ram on MPU board (speech doesn't work)

ordered capacitor for power supply.

IMG_20240409_104743 (resized).jpg

Replaced the capacitor on the powersupply board.

Placed sockets for audio sram
placed U25 NVram

used old sram from U25 for audio/speech

Also, MPU board NEEDS to be placed with ALL screws. Learned that the hard way. Else, you can have issues.

Seems to work now.
I might run a burn-in test to check the system.

Still need to fix the bel. --> bel OK
Knocker should be repaired, wire on connector was broken, i still have to place back.

Lot of work to:
Cleaning
Lamps
Rubbers.

Yes, indeed, i have noticed that later
Diagnostic needs to be pressed with door open.