Category Archives: RetroChallenge
My RC2015/01 project is to reverse-engineer and restore a 16-bit microcomputer (not a minicomputer!) that was sold in 1976, and design and build a memory upgrade and serial interface for it. If there’s time left after that, I’ll try to … Continue reading
My primary accomplishment for this RetroChallenge was making substantial improvements to my standalone floppy disk formatter program for the Quay 900. In the course of trying to find information about the Quay, I created a consolidated advertiser index for the … Continue reading
Mostek published a great little Z80 reference card called the “Z80 Microcomputer System Micro-Reference Manual”. In addition to the Z80 CPU, it covers the PIO, CTC, and SIO, but not the Z80 DMA. Unfortunately it’s long out of print, so … Continue reading
I’m way behind on reporting on my Retrochallenge project, but I have been working on it. As Dr. Asimov wrote, “Sloane’s Teddy Wins the Race.” I’ve made progress porting CP/M to the Quay 900. I’ve improved my disk routines, added … Continue reading
I put some better error recovery code in floppy disk formatter for the verify pass. Previously I was getting verify failures on drive 0 when using double density, and the new code reveals that some of them are cleared up … Continue reading
Mark Wickens asked for photos. I haven’t taken many, but here are two.
I did a lot of cleanup of my floppy routines, and got the formatter working with double density. Right now it only runs as a “standalone” program. Once I have CP/M running on the Quay, I’ll put in conditionals to … Continue reading
I’ve added volume 2 to the BYTE consolidated advertiser index. It is provided as an ODF (Open Document Format) spreadsheet.
I’ve been compiling a consolidated advertiser index for the early years of BYTE magazine, thus far from V1N1 (September 1975) through V2N3 (March 1977). Hey, that’s one more thing to add to my Retrochallenge project! This did turn up some … Continue reading