RTcom Radio Modems - Manual (Page 13)

13
CONNECTIONS
Data connections should always be made using screened cable. This will insure maximum rejection of
interference from outside sources. Always use a common ground point.
The RTcom Global, Eurpoa, MAX and Outback modems support RS232, RS422 and RS485
communications, both 2 and 4-wire. The RS232 port should be used for short cable runs of up to 10m
and the RS422 and RS485 can be used for over 100m. The modems support various data rates from
1200 to 9600bps depending upon version. All units support 7 and 8-bit ASCII even an odd parity and 1
or 2 stop bits.
Terminal Number Designation WRT Modem Notes
1 +24V dc supply
2 GND Ground
3 +12V dc supply
4 GND Ground
5 DTR** Optional not
normally needed
6 DCD Optional not
normally needed
7 TXD (RS232) Output data from
modem
8 RXD (RS232) Input data to
modem
9 Z = TX (-) RS485/ RS422
10 Y = TX (+) "
11 A = RX (+) "
12 B = (RX(-) "
13 GND Ground
Connections for the Global and Max modems
Terminal Number Designation WRT Modem Notes
1 +24V dc supply
2 GND Ground
3 +12V dc supply
4 GND Ground
5 TXD (RS232) Output data from
modem
6 RXD (RS232) Input data to
modem
7 Y TX(+) RS485/ RS422
8 Z TX(-) "
9 B RX (-) "
10 A (RX(+) "
11 GND Ground
Connections for the RTcom-Europa Modem