GE MDS SD Series Technical Manual page 33

NOTE In addition to RS-485 mode, the radio is capable of operating in RS-422 mode. RS-485
must be selected in the menu, and the pin descriptions/wiring arrangements shown in
Table 9 apply.
NOTE The radio is hard-wired as a DCE device.
Table 8. COM2 Pin Descriptions — Radio in RS-232 Mode
Pin Radio Input/
Number Output
1 OUT
2 OUT
3 IN
4 IN
5 --
6 OUT
7 IN
8 OUT
9 --
Table 9. COM2 Pin Descriptions — Radio in RS-485 Mode
Pin Radio Input/
Number Output
1 OUT
2 OUT
3 IN
4 IN
5 --
MDS 05-4864A01, Rev. I
Figure 21. COM2 Connector (DB-9F)
As viewed from outside the radio
DCD (Data Carrier Detect/Link) — A high indicates signal received.
RXD (Received Data) — Supplies received data to the connected device.
TXD (Transmitted Data) — Accepts TX data from the connected device.
Sleep Mode Input — Grounding this pin places the radio in a low power
consumption mode.
Signal Ground — Connects to ground (negative supply potential) on chassis.
Alarm Output (DSR) — Behavior is user-configurable. Default behavior: An RS-
232 high/space (+5.0 VDC) on this pin indicates an alarm condition. An RS-232
low/mark (–5.0 VDC) indicates normal operation.
RTS (Request-to-Send) — Keys the transmitter.
CTS (Clear-to-Send) — Goes "high" after the programmed CTS delay time has
elapsed (DCE), or keys another connected radio when RF data arrives (CTS
KEY).
Reserved — User I/O for special applications
Carrier Detect/Link — A high indicates signal received.
TXD-/TXA (Transmitted Data -) — Inverting driver output. Supplies received
payload data to the connected device.
RXD-/RXA (Received Data -) — Inverting receiver input. Accepts payload data
from the connected device.
Sleep Mode Input — Grounding this pin places the radio in a low power
consumption mode.
Ground — Connects to ground (negative supply potential) on the radio's PC
SD Series Technical Manual
Pin Description
Pin Description
23