Pin 1: *Disk Ready
Pin 2: *Disk Read Data
Pin 3: Ground
Pin 4: Ground
Pin 5: Ground
Pin 6: Ground
Pin 7: Ground
Pin 8: *Disk Motor Control
Pin 9: *Select Drive 3
Pin 10: *Disk Reset
Pin 11: *Disk Change (Latched Low)
Pin 12: +5V (250 mA maximum.)
Pin 13: *Select Disk Side (0=Upper, 1=Lower)
Pin 14: *Write Protect
Pin 15: *Track Zero
Pin 16: *Disk Write Enable
Pin 17: *Disk Write Data
Pin 18: *Step (Pulse: Low, then high.)
Pin 19: Direction (0=Inner, 1=Outer)
Pin 20: Unused
Pin 21: *Select Drive 2
Pin 22: *Disk Index Pulse
Pin 23: +12V (160 mA maximum, 540 mA surge.)