Hitachi 902 Service Manual page 140

Designation
of Short Pin
DC Selection of J1-3, 4 pin output signal function
RY DC RY
O
S
O
DS0, 1 Drive selection
Function of short plug S: Shorted, O: Opened
S Output of READY signal
O Output of DISK CHANGE signal
O Open
Function
Function
6 - 6
(cont'd)