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Author Topic: Sys 80 Non CPU boot/IRQ issue  (Read 2589 times)

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Offline MartyJ

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Re: Sys 80 Non CPU boot/IRQ issue
« Reply #45 on: May 30, 2009, 01:45:24 PM »
New CPU in, couple of this resolved but still IRQ high.

From reading the schematic, IRQ begins at pin 4 U1 (6502) goes via R1 & R2 to pin 16 TC1 then to pin 25 U4, U5 & U6.

Is there anything prior  to U1 which has anything to do with IRQ?
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