Mike's PCjr Page

Okay, I figured something out....I isolated it to one chip on the board... resoldered it and still no dice. However, if I hold down a key, and lightly swipe a finger along the pins of the part, one the side facing the back of the keyboard, it will work...until I lift the key. The chip is a MC14068 w...

Does anyone have schematics for the chicklet keyboard in digital form? My keyboard has quit working... except when I press around certain areas of the PCB. Trying to figure it out right now. In the meantime, I'm using the "enhanced keyboard" and have found that I really like the chicklet o...

I did, right after I sent that.

Was there any software for the PC released on Cassette?

Are there any MP3/WAV recordings of PC and PCjr software out there somewhere?

Neat! I had no idea about the MISE project. I wonder if that could easily be adapted to work on the Coleco ADAM (my favorite classic home computer) since it's a Z80 based machine as well.

Well, it at least appears that they had DMA as an add-on expansion in mind when they designed the system, at least as far as the FDC is concerned since it's wired up for it on the expansion bus.

Hi. Is the jr floppy controller non-standard compared to an IBM PC? I have been trying to run the 22DISK utility to read/write CP/M disks for my Kaypro, and although it does recognize the jr floppy drive, it keeps giving out the error "drive not ready" when it tries to access it. When thi...

I have yet to do the Tandy mod myself, but looking at the schematic of the mod it should be easily reversible just adding a toggle SPDT switch into the circuit. The mod has you cut the trace going to pin 2 of ZM31, and wire the output of an XOR gate in an 74S86 package (pin 3) to pin 2 of ZM31 inste...

FWIW, I've done several transfers from the built-in FTP server in OS X Snow Leopard without trouble.

Thanks. mTCP is basically the project to run a Telnet BBS on a PCjr one day. The BBS exists but it needs a lot more work. The rest of the apps are just to fool people into testing my code for me. ; - 0 Ha! I was thinking this would be an awesome thing to do. I used to run a BBS ages ago using the R...