Beijing ART Tech A-GPRS1090I, User Manual

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A-GPRS1090I User’s Manual Version: 6.021
based on connection method of communication, the two communication sides are equal, either part after receives each
other's data packets need not response. Because the communication process is simplify, so speed of UDP communication
is faster, however stability and data reliability are not better than TCP communication.
When using TCP to establish connection, the module servers as a TCP client, data center server as a TCP server, under
this mode, module has landed data center server can exchange data ; while in DTU communication, it does not exist
above relationship , module and data center must establish a UDP connection. Because the module in the mobile operator
network, so the public network (Internet) on the network equipment can not communicate the module direct lily, in such
circumstances, only the module takes the initiative to connect public network equipment, when module uses UDP mode
to send data to the data center, data packets will carry the IP address and port number information, after data center
receives packets, it can establish a new connection between module and UDP according to this information , when
establishment is successful, two sides can exchange data . However, because UDP mode in GPRS environment is
instability, easy losses packets, so I do not recommend using UDP mode.
SVR1IP1, SVR1NAM1, SVR1PORT1, CNTMODE1
A target server configuration includes IP address and port number, if the server does not have a fixed IP address, you can
use the domain name. When the server's IP address validity, the domain name will be ignored. If it is failure after several
attempts to connect the main central server, the module will automatically switch to connect the backup center server.
When use backup server, if the long- distance configuration connection suddenly disconnected, the module will
re-connect the backup server. If it is working when the connection suddenly disconnected, the target server will switch
back to the main central server.
TRYCNT
，
TRYTIM
，
TRYSPAC
In order to increase the security of data center, it will send a packet which is referred to "Registration packets" when the
module lands on the target server. Registration packets contain parameters, if user software finds the secret code is wrong,
it can refuse equipment to land. Secret code can be set to any 8-byte characters.
The number of the same goal’s connecting which in the same group connection, is controlled by the number of target
re-connected. “0” stands for regardless of batch when establishes connection (parameters of connection interruption
interval is invalid). The interval of target connection is used to control the time between two connections, the smallest
time is 10s, and the longest time is 65.5536s. The interruption interval of target connection is used to control the time of
two groups’ connections, the smallest is one minute, and the longest is 65,534 minutes.
For example, assume that now configure the number of re-connection is 5 times, re-connection interval is 200s, the
disruption of re-connection interval is 10 minutes, the IP of the main data center, the back-up data center and port
number are set. Then the module will first try to connect the main data center, if the connection is fail, it will be in 200s
interval to attempt to connect the main data center, until five opportunities are used up. Next, the module will delay 200s
to switch the target server, after that it will try to connect the back-up center, if the connection is fail also, it will attempt
to connect the back-up center in 200 seconds interval, until five opportunities was run out. So far, a number of
connections are end, the module into the delay of "Connection interrupted interval", after delays 10 minutes it will repeat
the process to start the next batch of connection attempt. Until the modules connect to the server successfully.
SERBAUD
This parameter controls the module serial’s communication baud-rate, you must use the standard baud-rate for
communication, and baud-rates are supported as shown in Table
3.13
.
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