Raveon RV-M8R, Техническое руководство

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Company Confidential 9
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
M8S modem.
There is also a “Command Mode” used to program and configure the
M8 . In
the Command Mode, the M8S modem accepts commands via the serial port
TxD pin. The commands can be used to change certain internal parameters
of the
M8S modem as well as to read-out the current configuration and
diagnostic statistics.
4.2. Command Mode
The M8S
modem may be put into a “Command Mode”, by entering a
sequence of three plus characters (+++). To keep the M8S 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 M8S modem first enters the Command Mode, it sends the phrase
Raveon M8S
(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)