That's a blast from the past! I cut my teeth on an Apple //e so maybe I can provide some insight. Typically on startup, the Apple 2 series would display a bunch of junk on the screen and then clear it, with Apple ][ or Apple //e at the top of the screen. It would then boot Dos 3,.3 or ProDOS from whatever floppy drive you had. IIRC, the transition between screen garbage and the black Apple .//e screen happened when the system loaded and ran the system ROM. So my guess is that there is something wrong with the ROM. You are probably right about moisture.
It may be possible to repair. I would take a look at references from KansasFest. It is meeting of Apple II enthusiasts that discusses stuff like restoring and repairing old Apple II systems, among other things. For example: https://www.youtube.com/watch?v=MFfjdIWe...
"So You Want To Repair Your Apple II — Jay Graham — KansasFest 2017"
You may be able to connect with some of these folks. Jay Graham appears to be The Man when it comes to repairing/restoring Apple II systems. His twitter handle is @jwg1962
That community may also be good sources for the technical manuals and other info. I would start here: https://a2central.com/category/help/
I hope this sends you in the right direction.
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Can you give us a bit more here. Is the system working now?
Dan さんによる
No not working. Turn it on and get garbage on the screen, mixed characters all over. Was working until I left it in the shed, maybe moisture got to it?
So could be anything, ram? I’ve got an oscilloscope but can’t see anything obvious. Clock ok. Data and address lines active. Not sure where to look.
Back to the original question.
peter.drury1952 さんによる
I'm pretty much convinced the problem is in running he autostart rom. You might be able to dump into integer BASIC from your hung starting screen. Try pressing ctrl-b and then return. If it works, you'll get a ">" and a blinking cursor.
I found one book with my old //e that might help, and better still I found a pdf copy of it online. It is the Apple II reference manual:
http://www.classiccmp.org/cini/pdf/Apple...
In the process of finding the pdf, I found other sources that might help. Apple 2 circuit description:
https://apple2online.com/web_documents/A...
and How to repair and maintain your apple computer.
https://apple2online.com/web_documents/H...
You might also find useful the Apple //e repair guide. Which admittedly seems better at finding the problems than repairing them https://www.apple2online.com/web_documen...
Michael Clark さんによる
Thanks Michael Clark! My initial question has now been answered. Hard r software reset. Nearly the first page of the apple book tells me that the reset key on the keyboard is not being read by the microprocessor but is a direct connection to the cpu reset. Bugger. Was
Hoping it was reading the keys. I havnt used my apple for years so i will have to read more. Im absolutely wrapped in the info you have found me. Will do some more checking and let you know how i go. Might be a while but ill be back.
peter.drury1952 さんによる
I'm really glad that these references have helped. I was impressed by the amount of documentation on the Apple2onine site though at times it seemed to have problems loading, and firefox seemed to do a better job with it than Safari. But given the amount and depth of information it was worth dealing with a few quirks. They have a forum as well but I saw you have to register and then mail the sysop to let him know you are not a bot. Finally, you might find this site on Apple II repair to be helpful as well: https://www.willegal.net/appleii/appleii...
It includes a case example of debugging a problem that seems very similar to yours.
I wish you the best of luck and I'll keep an eye out to see how progress goes.
Mike
Michael Clark さんによる
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