Thread: Up and Running
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Old 06-18-2008, 08:53 PM
Geoff Harrison Geoff Harrison is offline
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Join Date: Feb 2007
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Ok, I knew I wasn't (completely) crazy. You can run the front panel without the CPU, but you have to pull BA (CPU pin 7) high. I removed my 6800 and connected CPU pin 7 to pin 4 (IRQ) which is tied high through a 3.3k resistor, and my front panel works fine.

Does anyone know why it worked for me once and then stopped? BA is driven through CMOS buffer PP, can a CMOS buffer whose input is floating drive its output high some times and low other times, at random?

Geoff.
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