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It won't boot because the disk is missing track 2. Track 2 should be DD with fifteen 512 byte sectors, but it only has a single 128 byte sector which is a copy of the first sector from track 1. Oddly there is another copy of CP/M 2.24A in TD0 format that is dated a couple of years earlier which...

I would also like to get images for MP/M II for the Altos 8000.

After spending a bunch of time disassembling the HARDS8 tool and messing around with setting breakpoints and trying to make sense of the convoluted logic of both the hard drive controller and the software, I decided to take another approach. I went through all the 74xx chips on the controller...

It's a 10MB 1004. Possibly, but it will probably be a lot of work, and I'm not holding my breath that I'll ever get any data from it. I do intend to come back to it, but I could already see just going through the troubleshooting steps was going to be a very long project in itself, and sourcing...

Ah, so there was a "secret" way to do it! Thanks for the info. I didn't realize there was a B2I file that would allow specifying more detailed information than could be passed on the command line. I was able to replace the OS tracks on one of the Altos disk images and write it out and it booted...

No, that's not the question, I've been working with images that contain multiple encodings too. The challenge is if there is a way to create an .IMD with multiple encodings without reading it in from a physical disk. I have raw sector images that I'd like to convert to an .IMD with different...

It seems like it's pretty common for CP/M systems that supported double density MFM to use FM encoding on the first two tracks, and then MFM encoding on the rest of the tracks. Or sometimes they use 128 byte sectors for some tracks, and larger sector sizes for other tracks. As I'm trying to get...

A couple of weeks ago I finally came back around to working on my Altos 8000, after seven years of sitting on a shelf unused. Mine uses an 8500 model board, and came with a single floppy and an SA1000 10MB hard drive and the hard drive controller. I've managed to get it booting into the ROM...

A project that I've had set aside for a while was seeing if I could get my Victor 9000 booted using boot images that were uploaded by danielj a few years ago. I spent some time researching how to convert the images to something that I could write with either my SuperCard Pro or FluxEngine, but...

Not sure how to spec out a replacement for a long obsolete transistor. The Disk ][ & III analog board and the Apple III motherboard use MPS-U51 5W PNP transistors with base in the middle. What's the modern equivalent? MPS-U51 datasheet...

Do any of you happen to have a Prometheus Versacard for the Apple II? I'm having some problems with mine and it's beginning to look like the EPROM has gone bad. When I boot up ProDOS it crashes most of the time. Doing a disassembly on the ROM from within the Apple II shows garbage instructions...

I acquired a Dataspeed Conductor floppy controller about a month ago in order to install it in my IMSAI with the JAIR 8080 so I could hook up some 8" floppy drives. Fortunately it came with a manual, schematics, and an example BIOS for CP/M 1.4. I've been fighting with it for quite a while...

It's time for another type-in BASIC program challenge! Are you ready for BASIC Week 3: Under the Sea? This time around instead of just being a picture or an animation, it's a game! You take control of a sea turtle in a sort of endless runner type game. The turtle constantly swims from left to...

I recently acquired a Model 1 with monitor but without power supply. I've currently got it on my bench powering it off another power supply. When I tried it out the first time the video wouldn't sync, but I could just make out MEM SIZE? and see that I could type things. I hooked up Z5 and Z6 to...

I put together a video of my Raspberry Pi acting as a Commodore 64 disk drive. It works without using an external microcontroller, the IEC bus is interfaced directly to the GPIO pins on the Raspberry Pi. This essentially turns a Raspberry Pi into a NAS or SD card reader for a Commodore 64. No...