ESDI

pinout

ESDI=Enhanced Small Device Interface. Developed by Maxtor in the early 1980´s as an upgrade and improvement to the ST506 design.

34 pin IDC male connector  at the controller (control connector)

(At the controller) (At the harddisk) 20 PIN IDC MALE at the Controller. 20 PIN IDC FEMALE at the Harddisk. Control connector Pin Name Description 2   Head Sel 3 4   Head Sel 2 6   Write Gate 8   Config/Stat Data 10   Transfer Acknowledge 12   Attention 14   Head Sel 0 16   Sect/Add MK Found 18   Head Sel 1 20   Index 22   Ready 24   Transfer Request 26   Drive Sel 1 28   Drive Sel 2 30   Drive Sel 3 32   Read Gate 34   Command Data Note: All odd are GND, Ground. Data connector Pin Name Description 1   Drive Selected 2   Sect/Add MK Found 3   Seek Complete 4   Address Mark Enable 5   (reserved, for step mode) 6 GND Ground 7   Write Clock+ 8   Write Clock- 9   Cartridge Changed 10   Read Ref Clock+ 11   Read Ref Clock- 12 GND Ground 13   NRZ Write Data+ 14   NRZ Write Data- 15 GND Ground 16 GND Ground 17   NRZ Read Data+ 18   NRZ Read Data- 19 GND Ground 20 GND Ground

34 pin IDC female connector  at the hard disk (control connector)

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