11 Jul
2018
11 Jul
'18
11:12 a.m.
Anyone know where the Step/Direction version of the FDD interface
originated.
So far as near as I can tell the earliest FDDs (IBM 23FD Minnow and Memorex
650/651) used Step In/Step Out. The IBM 33FD Igar used direct control of the
motor.
The earliest Step/Direction FDD I can find is the Shugart 800 which first
shipped in September 1973.
Tom