CipherLab 8000 GPRS Cradle, Reference Manual

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8000 GPRS Cradle Reference Manual
1.2 DIAL MODES
When the mobile computer is seated in the cradle, it can send the collected data back to
a remote server, as well as download lookup files, via GSM or GPRS.
When dialing out ( ATDT ), the LED of Link will flash at the time interval of 0.3 seconds for
about 20 seconds. When connected, the LED of Link will be green after successfully
establishing a connection. The LED of Tx/Rx will flash as long as data transmission
occurs.
Note: It is suggested to issue the command “ AT ” every five seconds for best practice, in
order to check whether the mobile computer is seated in the cradle.
The escape sequence, consisting of three characters “ +++ ”, is used to terminate
the data connection.
1.2.1 GSM CONNECTION
When initialization is done, issue ATDT (phone number) to establish data connection via
GSM.
1.2.2 GPRS CONNECTION
When initialization is done, issue ATDT xxx.xxx.xxx.xxx:kkkk or ATDT [HostName:Port] to
establish data connection via GPRS. The buffer size of the cradle is 1460 bytes, and data
packet will be sent out as long as it satisfies any of the following requirements:
buffer is full (= maximum packet size is 1460 bytes)
delimiter character is encountered
end of transmission timeout (= no transmission for 5 milliseconds)
Due to the limited memory size, the cradle cannot send three packets at the same time,
and therefore, the third packet will be discarded. We suggest you enable the
Challenge-Handshake Authentication Protocol (CHAP) setting for best practice.