User's Manual

Company Confidential 11 Raveon Technologies Corp.

4. User Serial Port Commands

4.1. Overview

The serial portion the RF modem is used to send and receive data over the

air, as well as to configure the RF modem. In normal operation, the user

sends data into the TXD pin of the IO connector, and this data is transmitted

over the air. Received data from another RF modem is output to the user via

the RXD pin of the IO connector. This is the default operating condition of the

RF modem. No special characters, hardware control lines, or timing is

required to operate the RV-M80-EA2 modem.

There is also a “Command Mode” used to program and configure the M8. In

the Command Mode, the RV-M80-EA2 modem accepts commands via the

serial port TxD pin. The commands can be used to change certain internal

parameters of the RV-M80-EA2 modem as well as to read-out the current

configuration and diagnostic statistics.

4.2. Command Mode

The RV-M80-EA2 modem may be put into a “Command Mode”, by entering a

sequence of three plus characters (+++). To keep the RV-M80-EA2 modem

from unintentionally entering the Command Mode because of the +++ pattern

occurring in a stream of data entering the modem, there must be a pause in

the data stream before the +++ as well as a pause after the +++ is sent. If

either pause is missing, the modem will not enter the command mode.

Using serial communications software such as HypterTerminal, send the 3-

character command sequence “+++” while observing times of silence before

[BT (Silence Before Sequence) Command] and after [AT (Silence After

Sequence) Command] the command characters. The default BT and AT

times are 500mS.

The default sequence for entering into AT Command Mode:

1. No characters sent for ½ a second.

2. Input three (3) plus characters (“+++”) within ½ of a

second.

3. No characters sent for ½ a second.

When the RV-M80-EA2 modem first enters the Command Mode, it sends the

phrase

Raveon RV-M80-EA2 (transceiver version)

Raveon M8R (receive only version)

out of its serial port, and then an “OK” sequence. The “OK” sequence is a

sequence of 4 characters:

An “O”, “K”, <CR>, and <LF> characters

(<CR> = ASCII 0D, <LF> = ASCII 0A)