Recent content by btb

Thanks for adding that @Arbee! If it was ever uploaded before, I sure couldn't find it. It does seem a little crazy to leave out any slot IRQ line, but I guess they were just completely positive they never wanted to re-use the Eagle, like in a more capable machine.

Most of the pds slot signals from similar machines are straight off the cpu, so no problem connecting those, however I think one or two are handled by the V8 or other ASICs - not sure if they are strictly necessary, or if they might actually be already present on some unused EAGLE pins. Someone...

I guess I can't edit my post. I've made a bunch of changes, and the link to the schematic is now https://github.com/btb/ClassicII/blob/main/ClassicIIRevB/ClassicIIRevB.pdf

I just double-checked it and yes, it should definitely be connected.

Thank you! Oh wow, I didn’t know that one was available, that should be pretty helpful!

Hey, if it’s plausible ill do it, haha

Having just reverse-engineered the whole thing, I can confirm that error on the DFAC. The via next to C11 doesn't go anywhere, this board is littered with such dead-ends. Presumably test points.

I depopulated (mostly) and reverse-engineered my badly-bombed Classic II, and here is the result: https://github.com/btb/ClassicII My schematic, as a PDF. I also made corrections to the Bomarc schematics as I went along. The PCB is fully layed out in KiCAD, and I'd like to do a "reloaded"...

Hi @Cedsrepairs! One thing you definitely need is a small second board which pulls the clock signal off one of the chips on the motherboard. As for desoldering the chips on your board - If you haven't done it yet and you do go through with it, try to get some clear photos of the board so we can...

It definitely has a handful of electrolytics. They're all tiny (though not surface-mount) so I don't think I have replacements handy. Any reason not to use tantalums if I have them around? I need to figure out something I can use to test caps without spending an arm and a leg...

I've got an AppleCD 300e Plus, and it works pretty well. I know you aren't really supposed to expect them to read CD-Rs, but this one does, albeit not very well. Interestingly, it often reads them only when "cold" - if I have a CD-R that won't read, I'll switch off the power to the drive, wait...