(Topic ID: 233867)

Can a B-11581 sound board be used in a Pinbot?

By FiatsRUs

3 years ago

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Topic Stats

  • 15 posts
  • 3 Pinsiders participating
  • Latest reply 3 years ago by uncivil_engineer
  • Topic is favorited by 2 Pinsiders


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#1 3 years ago

I have a Pinbot project that has a non-working sound board. The speach works, but there is no background music. I went to a fellow Pinsider's place and used his working Pinbot to test it as follows:

* Put all 5 of my game, sound and music roms in the working Pinbot (using all of that machine's boards) and everything worked fine.
* Put my suspect sound board in the working Pinbot and got the same result as in my machine: no music (ran the music test and started a game).
* One-by-one, swapped all of the socketed chips from working Pinbot's sound board to my sound board (still installed in the working Pinbot), with no change.
* Swapped the data cable end-to-end (it was the one with the working Pinbot). No change.
* I did the "diode test" on all of the non-socketed ICs and compared the results to those on the working sound board. All compared favorably.
* I installed new amps (2003). No change.

I am officially dead in the water with this one. I do have a known-to-be-working B-11581 from an Earthshaker. It has two ROMs installed and the Pinbot has only one at U4 on the sound. Can the 11581 be used in the Pinbot?

#2 3 years ago

Both sound boards are setup similarly with a D/A 1408 chip on them, so it may work. If it were me, I’d put your Pinbot U4 chip in it and try it. At worst the board won’t boot, and you won’t hear a tone at power up.

#3 3 years ago

Does the 11581 need to have jumpers changed to work with one ROM instead of two? The Earthshaker ROMs are at U4 and U19. The Pinbot ROM would populate only U4.

#4 3 years ago

From what I have found, Pinbot uses 256k memory chips. From what I have found, I believe this means you will have to remove jumper W2-W3. If the board has a W10-W11, that will need to be removed as well.

Here is what I found in the old RGP archives:

From Clay's System 11 Guide.
This along with some pictures and more information are found under the
"different generations" section early in the guide and are not located
under the very short sound board section later in the guide.

Sound Board Generations.
For the first System11 games the external sound board was known as a
"background sound" board, and the speech was handled by the CPU
board's separate 6802/6821 at U24/U9 sound driven computer. Also the
sound amplifier was on the CPU board. With System11a the external
sound board D-11581 was a new board and more robust, with the sound
amplifier used on this external sound board (though sys11a still had a
CPU mounted amplifier, it was not used). The D-11581 sound board uses
a 68B09E for the processor (and yes it must be a "B" and "E" version
68B09E chip to work, as the "B" gives a faster clock rate and the "E"
gives an extended instruction set). With System11b, the D-11581 sound
board had fewer parts (U6/U7/U18 not populated).

With System11c all of the sound circuits on the CPU board was removed,
and the external sound board did all the sound (and U6/U7/U18 were
again populated).

Note the sound board for system11a, b and c were the same board, but
not necessarily with the same on-board components. The best version is
the one with the most components (that is U6/U7/U18 popluated).
The D-11581 sound board has some jumpers, since the board can use
27128, 27256 or 27512 EPROMs. If W2 and W3 are removed (below chip
U4), the board is set to use 27256 EPROMs. If W2 is installed and W3
removed, the board is set to use 27512 EPROMs*. With this information
it may be possible to combine the Sys11a/Sys11b CPU board 27256 sound
EPROMs into a single 27512, and the external sound board 27256 EPROMs
U4/U19 into a single 27512. Then use a fully populated D-11581 sound
board jumpered for 27512 EPROMs with a system11c CPU board in a
system11a or system11b game (making the system11c CPU board just as
versatile as an earlier system11 CPU board).

* Ok so maybe I lied about the sound board using 27512 EPROMs. It
appears the system11c generation of the D-11581 sound board has two
additional W10/W11 jumpers. For the board to be set to use 27512
EPROMs, W10 is installed and W11 is removed (in addition to W2
installed and W3 removed). The problem is on older D-11581 sound
boards, there is no W10/W11 jumper. I believe this was the reason I
could not get an older D-11581 to work with 27512 EPROMs. The
schematics are of no help since this jumper is not shown. I believe
the W10 jumper installed just ties all the EPROM's pin 1 together, and
with W10 remove they are not tied together, and with W11 installed all
the EPROM's pin 1 are tied to ground. But I may be wrong about that.

Another twist to the D-11581 is the U1 D/A (Digital/Analog) converter.
This chips talks with the Yamaha sound chip at U3, using the sound
EPROMs as data, and plays the digital music the game designer wants.
But this U1 chip has a personality. As some may have noted, the
Williams D-11581 sound board is also used in some Williams video games
like Arch Rival. So it would be logical to think you could take an
Arch Rival's D-11581 sound board, load it with system11 pinball sound
EPROMs, and have a replacement sound board. Well you would think, but
it appears that is not the case. The U1 D/A converter is different for
Arch Rivals. I know because I tried to use an Arch Rivals D-11581
(27256 EPROMs) with Earthshaker EPROMs, and got some very interesting
sounds. The sounds were very much different and more rap/drum
oriented. It just did not work. Putting the Earthshaker U1 D/A
converter in the Arch Rivals board fixed the problem, and the board
then played the correct Earthshaker sound track.

#5 3 years ago

Thanks, great info. The 11581 had two 27256 ROMs in it, thus no jumpers at W2 or W3. I placed the single Pinbot ROM at U4, installed it in the Pinbot and the music is now working as it should, but now the voice is not working! BTW, the B-11581 is a newer board that does NOT have U6/U7/U18 populated. Could that present an issue using it with an 11a?

#6 3 years ago

Ok, that is odd. I *think* the voices were generated from the MPU sound section. The sounds from the MPU are then mixed with the sound board generated sounds in the amplifier section of the sound board. When I get home this afternoon I will look at both wiring diagrams and see if I can find a reason why they are not mixing.

#7 3 years ago

Off the top of my head, You may want to check the connection between J16 on the MPU board to J1 on the sound board. That feeds the input from the MPU to the sound board. I have a Whirlwind with a fully populated 11581 board in it at home and a Millionaire machine that uses the 11298 board in it. I may try to swap those around and see if I can get the 11581 working in the Millionaire.

#8 3 years ago

I flipped the cable end for end. No change. Flipped the ribbon cable also. No change. I am going to go through the original board and replace all of the chip sockets and test the board after each one is replaced to see if that is the issue with it not working. I'm running out of bullets!

#9 3 years ago

Red herring on the speech not working. I put the old sound board back in after replacing an IC socket. It still didn't work, but neither did the speech. I'll have to check what that issue is related to. Maybe I didn't get the speech ROMs properly installed when I got done with testing on the working Pinbot. I am reasonably confident that when I get that working, I will be able to use the 11581 for the music. I'll keep you informed.

#10 3 years ago

Well it sounds like you are tracking the problem down. I do have some good news. I swapped my fully populated 11581 board from my Whirlwind into my Millionaire. After installed it, I thought it wasn’t working because I didn’t get a boot tone, but when I went into test mode, all the music was there, and it appeared to work in game mode.

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#11 3 years ago

Great! I'm am confident it will all work if I can just get the speech working again!

2 weeks later
#12 3 years ago
Quoted from FiatsRUs:

Great! I'm am confident it will all work if I can just get the speech working again!

I am having identical issue as you. No sounds at all on pinbot. I do get the 1 test tone when i turn it on. That is it. I don't get any sounds when using s1 on CPU or using the tests at the coin door I too was wondering about swapping with a 11581 sound board out of swords of fury.

Did this solve your problem?



#13 3 years ago

If you are getting a tone on boot, your sound board is at least booting. There are two sound tests in the test menu: a music test and a sound test. The music test will test the sound board, and the sound test will test the sound circuits on the MPU. Do either of these test work?

#14 3 years ago
Quoted from uncivil_engineer:

If you are getting a tone on boot, your sound board is at least booting. There are two sound tests in the test menu: a music test and a sound test. The music test will test the sound board, and the sound test will test the sound circuits on the MPU. Do either of these test work?

No I don't get any sounds in the menu either.
Also get no sounds by pressing S1 on MPU.

#15 3 years ago

Since you are getting a tone at boot, it sounds like the Sound section of your MPU is not working. You can start by reseating the connections at 1J15 and the ribbon cable at 1J21. You could also try re-seating the sound roms and sound processor at U24, U21 and U22.

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