Chengdu Ebyte Electronic Technology Co.,Ltd.
E280-2G4T12S User Manual
Copyright ©2012–2021
，
Chengdu Ebyte Electronic Technology Co.,Ltd.
16
pull-up resistance of the module; the level
of the drain opening method is more
adaptable, and some cases may require an
external pull-up resistor.
1
TXD, AUX push-pull output, RXD pull-up input (default)
0
TXD, AUX Open Output, RXD Opening Enter
1
0
Transmit power (approx)
External power supplies must provide
100mA or more current output
capabilities and ensure that power ripples
are less than 100 mV.
It is not recommended to use less power
to send, and its power supply is not high.
0
0
12dBm (default)
0
1
10dBm
1
0
7dBm
1
1
4dBm
For example, the meaning of the serial number 3 "SPED" byte):
Bi-bits of this byte
7
6
5
4
3
2
1
0
Specific
value
(user
configuration)
0
0
0
1
0
0
1
1
Representative meaning
Serial passport bit 8N1
The serial port is9600
Aerial rate 10kbps
Corresponding hexadecimal
0
13
8 Hardware design
It is recommended to use DC voltage regulator power supply to power the module, and the power ripple coefficient is small, and
the module needs to be reliably grounded;
Please pay attention to the correct connection of the power supply positive and negative, such as reversing may cause the module
to be permanently damaged;
Check the power supply, make sure there is a need for the power supply voltage, such as exceeding the maximum, causing the
module permanent damage;
Check the power stability, the voltage cannot fluctuate significantly;
When designing the power supply circuit for the module, it is often recommended to retain more than 30% of the overhead, and
the whole machine is good for long-term stable operation.
The module should be as far as possible from the power supply, transformer, high frequency trace and other electromagnetic
interference;
High frequency digital trace, high frequency simulation line, power line must avoid the module below the module, if it is not
necessary to pass through the module, assume that the module is welded in Top Layer, Top Layer, Top Layer, Top Layer, Top
Layer (all pair of copper Get a good ground), must be close to the module number and walk in the Bottom Layer;
Assume that the module is welded or placed in Top Layer, which is also wrong in Bottom Layer or other layers, which will affect
the dispersion and receiving sensitivity of the module varying degrees;
Assuming that there is a device around the module that there is a large electromagnetic interference will also affect the
performance of the module, and the intensity of interference is advised to remotely depending on the module. If the situation
allows appropriate isolation and shielding;
Assuming that there is a wire (high frequency digital, high frequency simulation, power line) around the module (high frequency
numeral, high frequency simulation, power line), which will greatly affect the performance of the module, and the intensity of
the interference is recommended to properly away from the module. If the situation allows for appropriate Isolation and
shielding;
If the communication line uses 5V level, it must be connected in series 1K-5.1K resistance (not recommended, there is still
