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Project: Apple IIc video/boot problem

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SO I have a new project IIc.


When I power it up I get no disk drive spin, just power and vertical color bars.


After disassembling it I found an anomaly at the location of the character ROM socket.


The socket is a 28-pin.


The chip in it is 24-pin, labeled 342-0265-A, and if i move it around slightly it get variations in the video output.


I believe this chip may be a video ROM chip for a IIe enhancement kit? (No real knowledge here, just a google search).


Is this the correct chip for the IIc?


Any help would be great.



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  • 3 weeks later...

If you're getting no disk drive spin, no beep, the problem isn't in the character generation circuit.


Your CPU most likely isn't starting up, so suspect a failed keyboard (holding Ctrl-Reset, or having the keyboard unplugged, can cause those symptoms IIRC), failed CPU, failed ROM, or failed first bank of RAM (IIRC in that order). Could also be the IOU or MMU, but that's getting lower in likelihood IIRC.

Edited by bhtooefr
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