GE MDS SD Series Reference Manual page 27

MDS 05-4846A01, Rev. C
Table 7. COM2 Pin Descriptions—Radio in RS-232 Mode
Pin Input/
Number Output Pin Description
1 OUT DCD (Data Carrier Detect/Link)—A low indicates signal
received.
2 OUT RXD (Received Data)—Supplies received data to the
connected device.
3 IN TXD (Transmitted Data)—Accepts TX data from the
connected device.
4 IN Sleep Mode Input—Grounding this pin places the radio in a
low power consumption mode.
5 -- Signal Ground—Connects to ground (negative supply
potential) on chassis.
6 OUT 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.
7 IN RTS (Request-to-Send)—Keys the transmitter.
8 OUT 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).
9 -- Reserved—User I/O for special applications
Table 8. COM2 Pin Descriptions—Radio in RS-422/485 Mode
Pin Input/
Number Output Pin Description
1 OUT Carrier Detect/Link—A low indicates signal received.
2 OUT TXD+/TXA (Received Data +)—Non-inverting driver output.
Supplies received payload data to the connected device.
3 IN RXD+/RXA (Transmitted Data +)— (Transmitted Data +).
Non-inverting receiver input. Accepts payload data from the
connected device.
4 IN Sleep Mode Input—Grounding this pin places the radio in a
low power consumption mode.
5 -- Ground—Connects to ground (negative supply potential) on
the radio's PC board.
6 OUT Alarm Output—Behavior is user-configurable. Default
behavior: A high on this pin indicates an alarm condition; a low
indicates normal operation.
7 IN RXD-/RXB (Transmitted Data -)— Inverting receiver input
8 OUT TXD-/TXB (Received Data -)—Inverting driver output.
9 -- Reserved—User I/O for special applications
COM2 PORT NOTES & WIRING ARRANGEMENTS:
RXD+ / RXA and RXD– / RXB are data sent into the radio to be transmitted out
•
• RXD+ / RXA is positive with respect to RXD– / RXB when the line input is a "0"
SD Series Ref. Manual (Packet & Transparent Mode) 19