AT&T 3B2/300 Technical Reference Manual page 756

Appendix: CONNECTOR AND CABLING I N F O R M A T I O N - - - - - - - - - - - - - - - -
20-PIN DAT A O CONNECTOR, J2
PIN DESCRIPTION
1 DRIVE SELECTED (DSD[O])
2 GROUND
3 NOT USED
4 GROUND
5
NOT USED
6
GROUND
7 CONNECTOR COMMON (J1Pl6)(J3P7)
8 GROUND
9 NOT USED
10 GROUND
11 GROUND
12 GROUND
13
+MFM WRITE DATA (MFMOPO)
14
-MFM WRITE DATA (MFMONO)
15
GROUND
16 GROUND
17 +MFM READ DATA (MFMIPO)
18 -MFM READ DATA (MFMINO)
19 GROUND
20 NOT USED
LEGEND:
MFM
NC
Modified Frequency Modulation
No Connection
B-174 TECHNICAL REFERENCE MANUAL
FUNCTION
INPUT
GROUND
NC
GROUND
NC
GROUND
GROUND
NC
GROUND
GROUND
GROUND
OUTPUT
OUTPUT
GROUND
INPUT
INPUT
GROUND
NC