Installation guide

20 PCM-4894 User Manual
Floppy drive connector (CN5)
You can attach up to two floppy disks to the PCM-4894's on-
board controller. You can use any combination of 5 1/4" (360 KB
and 1.2 MB) and/or 3 1/2" (720 KB, 1.44 MB, and 2.88 MB)
drives.
The PCM-4894 CPU card comes with a 34-pin daisy-chain drive
connector cable. On one end of the cable is a 34-pin flat-cable
connector. There are two sets of floppy disk drive connectors,
one in the middle, and one on the other end. Each set consists of
a 34-pin flat-cable connector (usually used for 3.5" drives) and a
printed-circuit board connector (usually used for 5.25" drives).
Connecting the floppy drive
1. Plug the 34-pin flat-cable connector into the CN5 connector.
2. Attach the appropriate connector on the other end of the cable
to the floppy drive(s). You can use only one connector in the
set. The set on the end (after the twist in the cable) connects
to the A: floppy. The set in the middle connects to the B:
floppy.
Pin assignments
The following table lists the pin assignments for the CN5 connec-
tor:
FLOPPY drive connector (CN5)
Pin Signal Pin Signal
1~33 (odd) GND 2 High density
4 +5V 6 High density
8 Index 10 Motor enable A
12 Driver select B 14 Driver select A
16 Motor enable B 18 Direction
20 Step pulse 22 Write data
24 Write enable 26 Track 0
28 Write protect 30 Read data
32 Select head 34 Disk change