⇡616kB 5.25” 77-track SSDD hard sectored
Back in 1980 Lanier released a series of very early integrated word processor appliances, the No Problem. These were actually rebranded AES Data Superplus machines. They were gigantic, weighed 40kg, and one example I’ve found cost ꆲ5bb4 of nearly ㇢1a6e
8080 machines with 32kB of RAM, they ran their own proprietary word processing software off twin 5.25” drive units, but apparently other software was available.
The disk format is exceptionally weird. They used 77 track, 32 sector, single-sided hard sectored disks, where there were multiple index holes, indicating to the hardware where the sectors start. The encoding scheme itself is MMFM (aka M2FM), an early attempt at double-density disk encoding which rapidly got obsoleted by the simpler MFM — and the bytes are stored on disk backwards. Even aside from the encoding, the format on disk was strange; unified sector header/data records, so that the sector header (containing the sector and track number) is actually inside the user data.
FluxEngine can read these, but I only have a single, fairly poor example of a disk image, and I’ve had to make a lot of guesses as to the sector format based on what looks right. If anyone knows anything about these disks, please get in touch.
fluxengine read aeslanier -s drive:0 -o aeslanier.img
- SA800 Diskette Storage Drive - Theory Of Operations: talks about MMFM a lot, but the Lanier machines didn’t use this disk format.