Radio Shack TRS-80 III - Page 110

Controller-to-Disk Drive
Ground
Signal
Description (Mnemonic)
1 2
(Spare)
3
4
(Spare)
5 6
(Spare)
(internal) (external)
9
10 SELECT 1,3
(DS1*) (DS3*)
11
12 SELECT 2, 4
(DS2*) (DS4*)
13
14
(Spare)
15 16 DRIVE-MOTOR ENABLE (MOTORON)
17
18
DIRECTION (DIR*)
19
20
STEP (STEP*)
21
22 COMPENSATED WRITE DATA (CWO)
23
24 WRITE
GATE (WG*)
31 32 SIDE SELECT (SDSEL)
33 34 (Spare)
Disk Drive-to-Controller
Ground
7
25
27
29
33
Signal
8
26
28
30
34
Description (Mnemonic)
INDEX PULSE (IP*)
TRACK 00 (TRK0*)
WRITE PROTECT (WPRT*)
READ
DATA (RD*)
(Spare)
TABLE 1. INTERFACE CONNECTOR PIN ASSIGNMENTS, J1 (external), J4 (internal)
Pin
1
2
3
4
Supply Voltage
+12 VDC
Return (+12 VDC)
Return (+5 VDC)
+5 VDC
102
TABLE 2. POWER CONNECTOR
PIN ASSIGNMENT