I have a TEAC FD50 - 5.25" Floppy Drive. From what I have found so far these drives were used in TRS-80 machines. Attempting to calibrate this drive using Kryoflux fails with error "Control command rejected by the device" + "CM: maxtrack=0".
When running dtc -c2 you can hear the drive spin up and see the disk start to rotate. But the Stepper motor just bumps out one step then back and never attempts to go any further. Unfortunately I am not 100% sure on the health of this drive, so unsure if this is expected behaviour or signs of a logic fault on the drive board.
Having checked the logic I can see Step and Direction both asserted by the Kryoflux, and the drive replys with Index and Track 0. (Drive Schematic Here: https://electrickery.hosting.philpem.me ... c_FD50.pdf)
Question is - what other pins is the Kryoflux watching for calibration to complete successfully?
BTW: Make sure you have the TEAC FD50A or FD50B as the FD50C and FD50D are 100 tpi drives! Yes and they are Single Density and the A and C modells are even Single Sided!
So what do you want to read with them?