Recent content by bladamson

Howdy folks. I am trying to design and build my own RC2014 / RCBus z180 system from scratch just for fun. There are 4 lines on the 80-pin RCBus that are used to daisy-chain interrupts and dma requests, for which jumpers are provided to change them between the daisy-chain configuration and...

I guess I will find out when it gets here, but I am impatient, heh. I have not seen this model with the built in speakers before. From the looks of the expansion bay, I am expecting a 486 or early pentium industrial board in a passive backplane.

As far as I know, all of the Kaypros other than the very earliest, possibly only the roman-numeral II, used the same universal motherboard, just with more or less of it populated. I don't know if my Kaypro Arabic-numeral 2 has graphics characters or not, but if it does not, I assume it's...

That is pretty rad.

Well a couple of them came apart into fewer than 5 pieces, so I guess there is enough left that I can JB weld all the breaks. So fragile! I've done Thinkpad batteries before with no issues, but these are being a real challenge. If I had the skills to model it, I'd 3d print a new battery pack...

Thanks, I'll give that a try.

Hey folks. I can't figure out how to disassemble these batteries (so as to rebuild them with new cells) without destroying them. I think they may be ultrasonically welded. :( Both the standard capacity and the folding extended capacity one. Any tips? If nothing else, I guess I can cut...

Yeah, my assumption is that it's straight through. I am assuming they're just looking for a 1:1 current balun and there isn't any voltage matching going on there, since I assume the impedance is the same on both coax ends. Presumably all they are doing is using the transformer to convert the...

Hitech C is pretty good. Almost-but-not-quite ANSI. You can run it on a modern OS with zxcc as a cross compiler, or native on CP/M.

If you go with the RC2014, just remember that the backplane has 40 pins per position, but some of the cards only have 39 pins per position. If you don't realize this and plug the card in 1-pin off, you'll destroy something. In my case it was the Z80 CPU. It's a cool project and I have nothing...

The RC2014 seems to be inexpensive and well-regarded, although it has some design shortcomings.

The terrible not-release of the Z800 really put a nail in CP/M's coffin I think. PCs were in the right place at the right time to pick up the ball that Zilog and DR dropped.

I used an old scsi enclosure for mine. All the scsi stuff still in there, so easy to convert back for the next guy. It had some knockouts in the back for audio connectors (I assume), so I just punched one of those out and hot glued the 'weazle in there.

I think there were two different keyboards. One may have been rubber dome? I can't remember. One of the more serious Tandy guys will chime in I am sure.

The switches go bad sometimes. They can be taken apart and cleaned, although it's kind of a pita. I think I'd try a bunch of deoxit and some exercise before I went to all that trouble, especially if it's only one key that's bad.