Adeunis RF ARF 73, Руководство пользователя

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UG_ARF73 V1.7
declared LOW.
In command mode, a response is sent (over the TXD line) according to the following DE/RE timing.
4. Radio communication
4.1. Radio communication
Radio communication is performed when the modem is set in transceiver mode (this is the default at power-up).
The radio data rate may be selected by AT command from 4800bps to 9600bps. 4800bps data rate offers a very
slow gain on the covered range, so 9600bps is the default radio data rate.
The output power may be programmed to 0.5W, 1W, 2W or 4W to either optimize covered range or power
consumption.
4.2. Radio channels
The S238 registers determined the center frequency of the bandwidth of the modem. The modem is calibrated
during factory process on this central frequency which can not be changed by using command mode. For this
reason, S238 is a read only register.
Bydefault,themodemisdeliveredwithapredefinedfrequencytablerecordedinS200register.Thecentral
frequency corresponding to the S238 register can be found in this table at position 8. First frequency of the table
is referred as position 0.
The frequency table can freely (with respect of 12.5kHz of spacing) be changed using command mode of the
product in a range of +/-3.5MHz around the central frequency displayed in S238. Note that the frequency must
be written with 4 digits after the point even if they are zeros. Each frequency must be separated by a space.
Up to 16 values can be entered. last value has to be ended by <CR> char.
The channel selected from the frequency table for radio transmission and reception is set in S201 register.
S201=0correspondstothefirstchannelofthefrequencytable,S201=15isthelastone.
Thepredefinedtableissetupwiththefollowingvalues:
Register S200 Frequency = S200 (MHz)
0 S238 – 400kHz
1 S238 – 350kHz
2 S238 – 300kHz
3 S238 – 250kHz
4 S238 – 200kHz
RS485 differential bus. When the last character has been transmitted on the RS485 differential bus, the lines are