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MTX-Java-T | 2019/2
MTX © by MATRIX ELECTRONICA S.L.U.
SUPPORT:
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3. DB9 Connector: I/O port
3.1 RS232
The MTX-Java-T modem is designed to be used as a DCE (data circuit-terminating equipment). Based
on the conventions for DCE-DTE connections, it communicates with the customer application (DTE- data
terminating equipment) using the following signals:
• Port TxD @ application sends data to MTX-3G-Java-T Terminal’s TD
• Port RxD @ application receives data from MTX-3G-Java-T Terminal’s RD
The RS232 interface is implemented as a serial asynchronous transmitter and receiver conforming to
ITU-T V.24 Interchange Circuits DCE. It is configured for 8 data bits, no parity and 1 stop bit and can be
operated at fixed bit rates from 300bps to 460.8kbps.
The electrical characteristics of the serial port signals are shown below:
PIN
SIGNAL
DIRECTION
DESCRIPTION
2
RD 0
Output
Received data
3
TD 0
Input
Transmitted data
5
GND
-
Ground connection
7
RTS 0
Input
Request to send
8
CTS 0
Output
Clear to send
9
VEXT
Output
Output voltage reference (4V)
Features (when connected to ASC0 or ASC1)
• Includes data lines TD1 and RD1 (2-wire/4-wire)
•
Includes the status lines RTS1 and CTS1 and supports hardware flow control (4-wire only)
•
The default configuration is 8 data bits, no parity and 1 stop bit. The setting can be changed
using the AT command AT+ICF and, if required, AT^STPB
•
Can be operated at fixed bit rates from 1200 bps to 921600 bps. Autobauding is not supported
• The default serial speed for MTX-Java-T is 115200bps