DECODE PRM4, Руководство пользователя

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4 AT command set
The device's parameters can be altered by using the AT command set. The commands
are sent to the device by using the terminal program (HyperTerminal or similar) over
the serial RS232 port at the speed 9600bps with 8 data bits, no parity, 1 stop bit. The
modem device accepts the commands only in
command mode. Changing the mode of
the device from data transfer to command can be achieved in two ways:

While turning on the modem, press and hold the SET button on the front
panel, – the device will start-up in the
command mode.

If the device is already turned on and in the data transfer mode, the command
mode is entered by sending the array that consists of the character repeated
three times within the given time frame. Before and after the array, the pause
in sending must be made. The pause intervals before and after the sequence
must be of the same duration. The default character for this purpose is ASCII
plus sign. Therefore, to enter the
command mode “+++” sequence ought to be
sent. The pause time interval is set in ms by using the ET command. The
default value is 1000 (or 1s). Bearing in mind the default setting, the
command
mode is entered by sending the following sequence:
pause 1s "+++" pause 1s
In both cases the modem will respond with OK when the command mode is entered.
If SET button is used for entering command mode, serial port parameters will be
fixed: speed 9600 b/s, format 8 data, no parity, 1 stop bit. If sequence "+++" is used
for the same task, modem will keep data formats used during
data transfer mode.
Each AT command consists of the command itself and, optionally, additional
parameters. At the end of each AT command, the Carriage Return (CR) character
must be sent. On keyboards, it is usually the new line or Enter key. The modem will
also accept the Line Feed (LF) character as well as CR LF and LF CR combinations.
The parameters can be entered in both the decimal and hexadecimal numeric systems.
For example, to set a network address both
ATNA10779 and ATNA0x2A1B can be
used.
By using the ATDC command, all set parameters and their values can be listed.
Below the manufacturer name and type of the device, the frequency range and
firmware release date are listed. The device output, as a result of
ATDC command, is
given in the following frame:
Radio modem PRM4 868MHz /User's manual V1.6 / 24.05.2011 12