User's Manual

WIT2410P

4. MODEM INTERFACE

Electrical connection to the WIT2410 is made

through a 16-pin male header on the modem

module. The signals are 3.3 volt signals and form

an RS-232 style asynchronous serial interface.

The table below provides the connector pinout.

Pin Signal Type Description

1 GND - Signal and chassis ground

2 TXD Input Transmit data. Input for serial data to be transmitted. In Control Mode

also used to transmit modem commands to the modem.

3 RXD Output Receive data. Output for received serial data. In Control Mode, also

carries receive modem status from the modem.

4 Input Configuration selector. Used to switch between Control and Data Modes.

Normally, CFG will be set for Data Mode. An internal 10K pull-up enables

Data Mode if this signal is left unconnected. Control Mode is also

accessible by transmitting an escape sequence immediately after wake

up or power up.

(0v) 1 = Control Mode

(3.3v) 0 = Data Mode

5 Input Request to send. Gates the flow of receive data from the radio to the user

on or off. In normal operation this signal should be asserted. When

negated, the WIT2410 buffers receive data until RTS is asserted.

(0v) 1 = Receive data (RxD) enabled

(3.3v) 0 = Receive data (RxD) disabled.

6 SLEEP Input Sleeps/wakes radio transceiver. In sleep mode all radio functions are

disabled consuming less than 50µA. At wake up, any user programmed

configuration settings are refreshed from non-volatile memory, clearing

any temporary settings that may have been set.

(3.3v) 1 = Sleep Radio

(0v) 0 = Wake Radio

Output Data carrier detect. For remotes, indicates the remote has successfully

acquired the hopping pattern of the base station.

(0v) 1 = Carrier detected (synchronized)

(3.3v) 0 = No carrier detected (not synchronized)

Output Clear to send. Used to control transmit flow from the user to the radio.

(0v) 1 = Transmit buffer not full, continue transmitting

(3.3v) 0 = Transmit buffer full, stop transmitting

9 - - Reserved for future use. Do not connect.

10 Input Resets the radio.

11-15 - - Reserved for future use. Do not connect.

16 VCC - Positive supply. Min 3.3 v, 5.0 v nominal, 10.0 v max.

RTS

DCD

CTS

CFG

Reset