Chengdu Ebyte Electronic Technology Co,;Ltd
E90-DTU (400SL22-GPRS) user manual
Copyright ©2012–2019，Chengdu Ebyte Electronic Technology Co,;Ltd
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3
、
Inquire the signal strength of the connection between the network module and the base station
Users can use the officially provided E90-DTU (400SL22-GPRS) configuration software. In the configuration mode
of GPRS/2G network transmission, click the "query signal strength" button to obtain the current signal strength
information.
4
、
Network function
Registration Package: registration packet off by default, the user can configure four registered package types,
optional respectively connected when sending a physical address, connection when sending a custom data,
additional physical address before every packet data, additional custom data before every packet data, custom
registration packet maximum length 40 bytes (when set to HEX format, the maximum length of 20 bytes).
a) In the idle state of network communication, heartbeat packet is used for network state maintenance. Its
heartbeat cycle can be set to 0~65535 seconds, and the maximum length of heartbeat packet is 40 bytes (when
set to HEX format, the maximum length is 20 bytes). Support two types of heartbeat: network heartbeat and
serial heartbeat. When network heartbeat is selected, it will start timing with communication idle and send
heartbeat packets to the server according to the configured heartbeat cycle. Select heartbeat as serial port, start
timing with communication idle, and send heartbeat packet to serial port according to configured heartbeat
cycle.
b) Clear the cache
：
before establishing a connection with the server, the data received by the serial port will be cached.
When establishing a connection with the server, you can choose whether to clear the cached data.
By default, clearing the cache will be closed. The maximum packet length from the local cache is
256 bytes.
7
、
The cloud transmission function of Ebyte IOT platform
Users can use the official E90 - DTU (400SL22 - GPRS) configuration software, GPRS / 2 G network
passthrough configuration mode, click on the "cloud passthrough" option, open module Ebyte cloud platform
passthrough function, after open, the user configuration information such as heartbeat, registration package will be
failure, users only need to a platform set up corresponding device passthrough forward relations between devices can
be realized data. For specific operation, please refer to the guide for transmission of Ebyte cloud platform.
8
、
Radio frequency function
( 1 )RF RSSI
：
Signal strength indicating function. Internal radio frequency module supports data packet
signal strength output. Can be used to evaluate radio frequency signal quality, improve communication
network, ranging. Support environment noise signal strength output to network server. Can be used to
manually implement LBT functions.
( 2 ) Radio frequency has FEC forward error correction algorithm: its coding efficiency is high, error
correction ability is strong, in the case of sudden interference, can take the initiative to correct the packet
interference, greatly improve the reliability and transmission distance; In the absence of an FEC, such packets
can only be discarded.
（
3
）
Networking function: this station can realize multi-level relay networking with E22 series modules or
E90-DTU (XXXSLXX) series stations. Multistage relay is suitable for ultra long distance communication.
Multiple networks are running in the same region at the same time, truly realizing the mutual forwarding of
multiple LANS to the Internet of things, and building the real Internet of things model. Please refer to the
chapter "application model" for details.
Summary of Contents for 400SL22-GPRS
Page 1: ...E90 DTU 400SL22 GPRS...
