A couple things if you have a volt meter test the power supplie voltages then see that the cpu has a "clock" pulse (on the 6502 is that on pin2 like the 6510?, look this up) a voltmeter should show about 2.5 volts on the clock pin (50% duty cycle of 5 V). Next if you have a working 8032 putting a dead chip in that will not fry the working unit, but that will tell you that have a working or dead chip (cpu, rom,via). Second the RAM is also a possible problem - but probably not socketed. Or you could have faulty logic ics 74lsxx again not socketed. --Ray > > >AV> This machine acts dead to the world. When powered up, the valve in >>AV> the back of the tube glows, but the monitor itself doesn't seem to >>AV> come to life. This may just be because I can't hear it whistle, >>AV> but I can ususally hear these tubes... Also, the startup beep is >>AV> missing, and blind-typing "?chr$(7)[cr]" has no effect. >> >>I think this narrows down the problem to the power supply, CPU, ROM >>or VIA. Well, not too narrow... > >Hmm... The PSU is (I think) OK - at least, there's some volts coming off >it. CPU/ROM/VIA - I've no idea how to check these. Well, I *could* swap >them with the other 8032 I've got, but I don't want to try that until I >know I'm not going to fry known good chips... > >Does funet have any chip pinouts? When testing voltages, it would obviously >be handy to check across the +ve and GND pins, rather than some signal pins... -- --------------------------------------------------------------- |Raymond C. Bryan 651-642-9890 vox | The battle is sometimes | |Raymond Computer 651-642-9891 fax | to the small for | |795 Raymond Ave -email: raycomp | the bigger they are | |St Paul MN 55114 @visi.com | the harder they fall. | |USA Amiga - Commodore | -- James Thurber -- | --------------------------------------------------------------- Message was sent through the cbm-hackers mailing list
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