User Manual

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16mA. In this mode, the module can automatically adjust the baud rate of wireless
transmission in the air according to serial port baud rate, and the corresponding
relationship is as shown in the table below:
Seri
al
port
bau
d
rate
1,200b
ps
2,400b
ps
4,800b
ps
9,600b
ps
19,200b
ps
38,400b
ps
57,600b
ps
115,200b
ps
Bau
d
rate
in
the
air
5,000bps 15,000bps 58,000bps 236,000bps
To get the farthest communication distance, the serial port baud rate can be set to be
low. For short-time transmission of mass data, set the serial port baud rate to be high,
but the communication distance will be reduced accordingly.
The receiving sensitivity of module at different baud rates in the air is as shown in the
table below:
Baud rate in
the air
5,000bps 15,000bps 58,000bps 236,000bps
Wireless
receiving
sensitivity
-117dBm -112dBm -107dBm -100dBm
Generally, every time the receiving sensitivity is reduced by 6dB, the communication
distance will be reduced by half.
When “SET” pin of module is at low level, the serial port transparent transmission
mode can be set through AT command (see the introduction in the following chapter
for details).
FU1 mode is relatively power saving mode, and the idle working current of this mode
is about 3.6mA. In this mode, the module can also set eight types of serial port baud
rate as shown in the above table, but the baud rate in the air is uniform, 250,000bps.
FU2 mode is power saving mode, and the idle working current of this mode is about
80μA. In this mode, the module only supports baud rates of 1,200bps, 2,400bps and
4,800bps, and the baud rate in the air is uniform, 250,000bps. If the module is set to
be other serial port baud rate, the module cannot conduct communication normally.