Honeywell HTRD400 Reference Manual page 166

Specifications and Connector Pinouts
Rev 1.02
Table E-2 25-Pin Interface Connector Pinouts
Pin COM connector (cont'd)
11 N/C
12 Auxiliary Ground. Reserved.
13 Auxiliary RS-232 TX. Reserved.
14 N/C
15 N/C
16 Power In to HTRD400 Recorder
17 Input Power Ground
18 N/C
19 Input Power Ground
20 N/C
21 Trigger 6
22 Aux RS-232 RX. Not supported.
23 N/C
24 Trigger 8
25 Trigger 7
152 Document 900.0328
05/05