Raveon RV-M80-EA2, Technical Manual

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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)
or
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)