I just picked up a 512 from a thrift store for $15, without a keyboard or mouse. I get it home, plug it in, and turn it on. The screen flashes the happy mac and then goes blank. The drive looks like it's trying to work but I can't really tell, and there's no beep. I find a paperclip and hit the interrupt switch, and first I get the happy mac, then I get the 0f000d code ("hey stop pressing that button there's nothing wrong"). Now, after I let go of the switch, the screen goes blank again. Brightness isn't the problem, and the display itself clearly works fine.
Any idea what could be causing this? Is it simply the lack of keyboard, mouse, and software, or do I have to crack the case and replace some capacitors?
I would definitely start with getting a boot floppy for it. Macs generally will boot and run just fine without a keyboard and mouse attached. If you still get the black screen after trying a known good boot disk, then something is definitely wonky with the circuitry -- I'd check the motherboard, since your monitor and analog board seem to be fine (if they were having problems, you wouldn't get any video at all).
according to sad macs, bombs, and other disasters...
qoute:
"xxxx000d Chip containing the serial and modem
xxxxxxxxx : ports (called SCC chip) failed"
Guess what? You will most likely need a hardware repair..."
so, throw the board
there is nothing yo can do to fix it, unless you have excellent soldering skills
I have a Mac 512K logic board that I will sell super cheap. I can ship this thing super cheap to anywhere in North America. The best part is that it has never been touched by Blackburn Group hands so it's completely void of evil.
PM me if you're interested.
"When you press the interrupt button on the side of your Macintosh when starting up, you should get a sad Mac icon with '0F000D' and some bits cycling under the icon indicating it is performing a memory test."
I don't think that's the problem. Looks more like an analog board failure coupled with some bizzare kind of short because the happy mac is appearing without any disk inserted whatsoever.
EDIT: either way I will probably sell it to anyone who's willing to cover the original price plus shipping, unless it's a really easy fix. It's been pointed out that the floppy needs fixing too, and I'm not really qualified to muck about in there with any of this stuff.
Would like to crack the case, just to see.