High Speed MPU

PUTTS5205

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OK I have searched hi and lo for a way to convert my recently acquired system 11a Pinbot MPU to 11 High Speed. From what I read it can be done and there are no components to buy, just things to move. Some grounds that are no longer used and sound pins that need to be added, but no one seems to tell the whole story.. Can anyone tell me a good on line guide to getting this done? I have had this game for two years now on the back burner. It's time to finish this one.
 
So here is the info I came up with (all from PinWiki.com). Firstly, the game will boot with High Speed roms put in it, no issues there. The System 11a only has 2 differences in it from its original counterpart System 11, 1)instead of the 7 segment diagnostic display on the board it is now 3 LEDs, and 2) the traces are modified on it to help make it forwards compatible with the upcoming 11A, 11B, and 11C. Your information about having to change some items was probably for 11A, not 11a (small difference ehh?). So go ahead drop your ROMs in, mount the board and fire it up. Come back here with any issues.
 
MPU swap

I have already tried it and it doesn't work. THere are no pins on the 11a(A) for the sound (1J15) has pins on the 11 but not on the pinbot board so I know there are things that need to be done.

I found this thread on pinside but no specific info "System 11 MPUs are the hardest to repair alkaline damage on. The traces to the displays run under the battery holder and are very fine. They are the first to go. As we all know, if you don't get every last bit of alkaline, it grows back.

You can modify an 11A MPU back to an 11. You'll need to add a few parts. Fortunately, the stock 11A MPU has all of the rare parts already on it, so you won't need to source those."
 
Hmm, I see what you are talking about. Here is the confusing part now, I found some info online and it doesn't even reference the 11a, just the 11A. It is saying all you would have to do is move 1J15, as U1 the audio amp is still present on the board, just doesn't have the 1J15. I guess my question becomes, if you plug everything else in except 1J15, does the game boot? If it does, then just remove 1J15 from your acid damaged System 11 board and move it to your 11a board. 1J15 is the wiring to your speakers, and will not affect the game from actually working.
 
To use sys11A mpu in a sys11, you need to add the connector 1J15 and install correct ROMs of course. Nothing else is needed.

If it doesn't work, then you have issues with your mpu.

Also, pretty sure there is no 11a and that's just a typo. Just 11, 11A, 11B, 11C.
 
board swap

I can only test it with the 1J15 unplugged as there are no pins on the 11a. I should also point out that I have the late 11 revision which had a jumper added w16. The 11a was only used in pinbot. I have an 11A as the 1J15 pins are not there they were there on early 11a's. Here is a Pinwiki quote referring to 11a.

"This CPU was only used in Pin Bot. It's actually a System 11 CPU with the 7 segment replaced by the factory with the 3 LEDs used in System 11A. The latest trace revision of this board also has the ground mod allowing it to work in any 11A/B/C game without modification. According to a friend it was referred to by the name of 11a instead of 11A by distributors."
 
transfer

That's the least of the issue though. THat should just give a portal for the sound to the speaker. The 11A is not booting.
 
Still confused

I still wonder what this poster meant on Pinside though" You can modify an 11A MPU back to an 11. You'll need to add a few parts. Fortunately, the stock 11A MPU has all of the rare parts already on it, so you won't need to source those " This leads me to believe that there is not just a simple add the 1J15 pins
 
The info I listed above came from the pinrepair guides.

Maybe the poster on pinside was confused with another version. 11C is the mpu that is missing the entire sound section. Populating it would be difficult due to hard to find parts.

Have you checked all of your voltages?
 
11a or 11A

From what I have found I have a hybrid Pinbot mpu because the 1J15 is not there but U1 is. The 11a does not have the pins at 1J15. The pinwiki pics show neither of the boards I have. They do not seem to be previously modified. Stampings on the board ar "genrad" and "14" in a circle.
 
mpu votages

Ironically the original acid damaged mpu comes up with "Adjustment failure" Good sign as for the voltages which is why i didn;t go there. although it is a ticking time bomb in it's current state. I bought this pinbot to replace it. I got it "pulled from a working machine" on ebay and it got shelved for later usage. I was ultimately only concerned with acid free not necessarily pulled working although that would have been nice. The pinbot board with High speed roms only comes up with random dashes in the displays.
 
Well the 11a thing is new to me. Thanks for info on it.

Sounds to me like you have a standard 11A MPU.

From pinrepair:
[FONT=verdana,arial,helv,helvetica][SIZE=-1]System11 Board System Generations. Short method to ID different system11 MPU boards:

  • "System 11" - connector at 1J15 (upper left corner).
  • "System 11A" - U1 present (audio amp), no connector at 1J15.
  • "System 11B" - U1 not populated, no connector at 1J15.
  • "System 11C" - entire sound section in upper left not populated, no connector at 1J15.
[/SIZE][/FONT]
Just to make sure, have you checked all the jumpers on the pinbot board and compared them to the acid damaged high speed?

How about the LEDs? Are you getting an error code?

Lastly, how bad is the acid damage on the current High Speed MPU?
 
Trouble codes

I found this about using 11a in 11.

"If a System 11 MPU with 3 LEDs is installed in a game whose original board contained the 7-segment LED diagnostic display first introduced with the System 7 board set, the status of the 3 LEDs won't help much. The game software is attempting to display a "0" (assuming your game boots correctly) on a 7-segment display. Since the board contains just the three LEDs, the MPU circuitry merely lights all three LEDs as shown in the picture at left. "

I am getting all three led's steady on.
 
Ah yes. Forgot about that.

Might wanna try putting the pinbot ROMs back in and booting on the bench. Then you can see if the board is booting correctly.
 
Ah yes. Forgot about that.

Might wanna try putting the pinbot ROMs back in and booting on the bench. Then you can see if the board is booting correctly.

And if you don't have the bench setup, do as I suggested, just plug your power in and your displays in, leaving the solenoids and switches disconnected, otherwise you could have some weirdo things happen.
 
rom swap

OK I will try the 11a with pinbotroms with only power and displays.
 
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