IBM 4840-563 System Reference Manual page 53

Pin No. Signal name
1 GND
2 +5V
3 GND
4 GND
5 N.C
6 DR0
7 MTR0
8 DIR
9 WDATA
10 GND
11 DRVDEN0
12 RDATA
13 N.C
14 N.C
15 N.C
16 N.C
17 INDEX
18 N.C
19 N.C
20 GND
21 STEP
22 WGATE
23 TRK0
24 WRTPROT
SurePOS 500 Model XX3 Technical Reference, v 1.3
I/O Signal Description
Power Ground
Power Supply
Power Ground
Power Ground
O Drive Select 0. Select drive 0.
O Motor Control 0
O Direction. Direction of head movement (0 =
inward motion, 1 = outward motion)
O Write Data. Encoded data to the drive for write
operations.
Power Ground
O Drive density select 0
I Read Data. Raw serial bit stream from the
drive for read operations.
I Index. Sense to detect that the head is
positioned over the beginning of a track
Power Ground
O Step. Low pulse for each track-to-track
movement of the head.
O Write Gate. Signal to the drive to enable
current flow in the write head.
I Track 0. Sense to detect that the head is
positioned over track 0.
I Write Protect. Sense for detection that the
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