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Skateball
Was working fine, went to turn it on and only get 3 flashes. No displays, but have glow indicating power present.
History: alltek MPU, LDB, SDB, all pins have been repinned w exception of display connectors.
All fuses are good
Voltages check at MPU & SDB, and display.
3 flashes points to RAM or PIA issue.
Switched out MPU with another MPU same issue.
Ideas?
Thanks
When swapping MPU no chips where changed.
Repeat of 3 flashes, tells me issue isn’t on MPU.
What should be my next move in trouble shooting this?
Quoted from westofrome:Are you swapping with another Alltek MPU with the DIP switches set for Skateball?
Yes
Quoted from barakandl:No 4th flash means the CPU cannot control all the PIA ports. If you switched MPUs and the problem remains the likely issue is something is shorted that is connected to the PIA.
Unplug the displays, sound board, lamp driver J4, solenoid driver J4. Power on and you should get all 7 flashes. Start plugging devices back in one at a time until you find what is making the PIA test fail.
Will do, appreciate the direction
Unplugged
all displays
LDB J4
SDB J4
Sound board
Still only get 3 flashes
Plug in another alltek MPU led stays on.
With only J4 connected on MPU I get only 3 flashes
Guessing this means problem is isolated.
Which chip (s) are likely problems?
Tried my 2 alltek boards that where failing in Skateball into Fathom both boards failed. Put original mpu into Fathom it worked fine.
So both alltek boards are bad 3 flashes, could a switch be stuck in skateball causing the alltek mpu failures.
Very reluctant to put another working mpu into skateball.
Thoughts?
I have some 6821 on hand. Will give that a try. The 6821 on alltek is U6 not U10 just making sure we are talking about the right chip.
Replaced 6821 connect one connector at a time no issues.
Once booting is complete it activates coils like a ball search one time. Tried another SDB same thing.
Put it in solenoid test mode passed.
Reboot 7 flashes no displays.
Will check voltages later this morning. Thinking something is shorting on PF
Quoted from westofrome:Have you tried resetting the Alltek MPUs?
Do you mean resetting push button on bottom of MPU?
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