Microwave Data Systems MDS TransNET 900 Installation & Operation Manual page 23

Typical RS/EIA-232 applications require the use of Pin 2 (receive
data—RXD and Pin 3 (transmit data—TXD). Some systems may require the
use of Pin 7 (Request-to-send—RTS).
detailed views of the
respectively.
If hardware flow control is desired, Pin 7 (RTS) and Pin 8 (CTS) may also be
connected. A more detailed discussion of pin functions is provided in
"Data Interface Connections (DB-9F)" on page
5
9 6
Figure 13. DATA Connector Pin Functions, EIA/RS-232 Mode
NOTE:
The data cabling between the transceiver and the connected device should be
kept as short as possible. For EIA/RS-232 operation, the maximum recom-
mended cable length is 50 feet/15 meters.
5 1
9 6
Figure 14. DATA Connector Pin Functions, EIA/RS-485 Mode
4. Measure and install the primary power for the transceiver. It must be
within 6-30 Vdc and be capable of providing 7.5 watts over this voltage
range. (Typical current draw is 510 mA @13.8 Vdc; 1.25A @6 Vdc.) A
power connector with screw-terminals is provided with each unit. Strip
the wire leads to 0.25"/6 mm. Be sure to observe proper polarity. The left
pin is the positive input; the right is negative. (See
CAUTION
POSSIBLE
EQUIPMENT
DAMAGE
MDS 05-2708A01, Rev. B
connector for EIA/RS-232 and EIA/RS-485,
DATA
Pin Function
1 1.....Data Carrier Detect (DCD)
2.....Receive Data (RXD)
3.....Transmit Data (TXD)
4.....Sleep (GND = Sleep)
5.....Signal Ground (GND)
6.....Alarm Output (+5/-5 Vdc)
7.....Ready-to-Send (RTS)
8.....Clear-to-Send (CTS)
9.....Reserved for Special Uses (Do not connect)
As viewed from outside the radio
Pin Function
1.....Not Used (Open)
2.....TXD + (Transmit Data +), Non-inverting driver output
3.....RXD + (Receive Data +), Non-inverted receiver input
4.....Sleep (GND = Sleep)
5.....Signal Ground (GND)
6.....Not Used (Open)
7.....RXD – (Receive Data –), Inverting receiver input
8.....TXD – (Transmit Data –), Inverted driver output
9.....Reserved for Special Uses (Do not connect)
As viewed from outside the radio
The radio must be used only with negative-ground sys-
tems. Make sure the polarity of the power source is cor-
rect. The unit is protected from reverse polarity by an
internal diode and fuse.
MDS TransNET 900 I&O Guide
Figure 13 and Figure 14
54.
Invisible place holder
Invisible place holder
Figure
show a
see
15.)
15