Chengdu Ebyte Electronic Technology Co.,Ltd.
E22-400T22DC User
Manual
Copyright ©2012–2019
，
Chengdu Ebyte Electronic Technology Co.,Ltd.
4-12
3
After switching to new operating mode, it will not work in the new mode immediately until AUX rising edge
lasts for 2ms . If AUX stays on the high level, the operating mode switch takes effect immediately.
4
When users switch to other operating modes from mode 3 (sleep mode) or it’s still in reset process, the module
will reset user parameters, during which AUX outputs low level.
5
Due to the characteristics of the LoRa modulation method, the information transmission delay is much longer
than FSK. For example, at 1.2kbps, the 100-byte transmission delay is about 1.5 seconds. It is recommended
that customers do not transmit large amounts of data at low airspeed in order to avoid data loss caused by data
accumulation and communication abnormalities.
6. Operating mode
There are four operating modes, which are set by M1 and M0, the details are as follows:
Mode(0-3)
M1
M0
Description
Remark
0
Transmission
mode
0
0
UART and wireless channel are open, transparent transmission is
on
Supports configuration
over air via special
command
1 WOR mode
0
1
Can be defined as WOR transmitter and WOR receiver
Supports wake up over air
2
Configuration
mode
1
0
Users can access the register through the serial port to control the
working state of the module
3 Deep sleep
mode
1
1
Sleep mode
6.1 Mode switching
No.
Remark
1
Users can combine M1 and M0 with high and low levels to determine the operating mode. Two GPIOs of the MCU can
be used to control mode switching;
After changing M1 and M0: If the module is idle, after 1ms, it can start working according to the new mode;
If the serial port data of the module has not been transmitted through the wireless, the new working mode can be
switched after the transmission is completed;
If the module receives the wireless data and transmits the data through the serial port, it needs to finish transmission
before switching the new working mode;
Therefore, mode switching can only be valid when AUX output 1, otherwise it will delay switching.
2
For example, users continuously input a large amount of data and simultaneously performs mode switching. At this
time, the switching mode operation is invalid; the module will process all the user data before performing the new mode
detection;
Therefore, the general recommendation is to detect the output state of the AUX pin and switch after 2ms when the
output is high level.
3
When the module is switched from other modes to sleep mode, if the data has not been processed yet;
The module will process these data (including receiving and sending) before entering sleep mode. This feature can be
used for fast sleep, which saves power; for example, the transmitter module works in mode 0, the user transmits the
serial port data "12345", and then does not have to wait for the AUX pin to be idle (high level), and can directly switch
to sleep mode. And the user's main MCU immediately sleeps, the module will automatically transmit the user data
through the wireless, and automatically enters sleep within 1ms;
This saves MCU's working time and reduces power consumption.
