8
Raveon Technologies Corp.
Front-view of DB-9 connector on modem (female)
Pin
Name
Dir
Function
Level / Specification
1
CD
out
Carrier
detect
If enabled, indicates presence of carrier. Logical 0 (+ voltage on RS-
232) means carrier is present. Logical 1 (- voltage) means no carrier
detected. If disabled, it is asserted (0) whenever the modem is
operational, and not in the configuration mode. It will be a 1 when the
modem is in the configuration mode.
2
RxD
out
Receive
data
Data out of the modem. It is the data received over the air.
3
TxD
in
Transmit
data
Data into the modem.
Also used as digital input IN2 for exception reporting. GND or floating
for a 0, >3V for digital 1. If enabled for digital inputs, the serial data
entering this pin is ignored (except in the command mode). Use the
TRIGBITS command to set which bits are used as inputs.
4
DTR
in
Data
terminal
read
Normally ignored by the
RV-M7
modem. May control the power-state
of the modem in low-power mode if this feature is enabled.
Also used as digital input IN0 for exception reporting. GND or floating
for a 0, >3V for digital 1. Use the TRIGBITS command to set which
bits are used as inputs.
5
GND
Ground
connection
Signal and power ground
6
DSR
out
Data Set
Ready
Normally is set to 0 when modem is powered on and running. Modem
sets to a 1 when in low-power mode.
7
RTS
in
Request to
send
or
IN
1
Used to stop/start the flow of data coming out of the modem TxD pin.
0 = OK to send, 1 = don’t send. Leave disconnected if not used.
Also used as digital input IN1 for exception reporting. GND or floating
for a 0, >3V for digital 1. Use the TRIGBITS command to set which
bits are used as inputs.
8
CTS
out
Clear to
send
Used to stop the flow of data going into the RxD pin from the device
connected to the
RV-M7
. 0 = OK to send, 1 = don’t send. If the
RV-
M7
cannot accept more data, it will negate this signal (level=1).
9
Power
In/out
DC power
User may supply the DC power to the modem on this pin.
Note: RS-232 signals use positive and negative voltages to represent digital 1s and 0s. A positive voltage is a 0,
and a negative voltage is a digital 1.
This pin-
out allows it to be directly plugged into a computer’s 9-pin serial port using a
conventional 9-pin RS-232 serial cable. To connect it to a modem, or peripheral that
has a serial port, you will need a “
null-modem
” cable.
3.2. Analog
[ A ] 5T838
The DB15 connector on the front panel has the following pin functions.
Pin# Function
Description
1
MIC
Analog Input
2
Audio Out
Analog Output
3
RSSI
Radio Signal Strength Out
4
IOC
General IO
– C
5
DTR
Digital DTR out
6
VIN
DC Voltage Input
7
V3
3./3V Output
8
RXD
RX data out, RS232 level
