User`s manual

A-GPRS1090I User’s Manual Version: 6.021
3 Click the “get information” button, then we can read the information of mode, or we can wait for seconds because it
can get information voluntarily.
4 In the left of user interface, there is a “local COM port configuration” tool, we can change the information in it, when
has been changed, we can save new information by clicking the “save configuration” button.
AT parameter configuration protocol
After DTU had entered the configuration mode, accordingly we can send command frames with configuration message,
by command frames we can read or write parameters. Command frames all use ASCII characters. This not only gives the
user convenient to use hyper terminal for parameter configuration in absence of configuration tool, but also allows user
to write the program of DTU configuration easily in his own device. Command frame structures are shown in
Table2.1.4-1. There are two categories of command, writing commands and reading commands. Writing commands are
used to configuration parameters of DTU, reading commands are used to query the current configuration of DTU. The
difference between them is that reading commands do not have configuration parameters and characters after the
command are different. "=" stands for writing command, means to evaluation. "?" sands for reading command, means to
inquiry.
Command codes are different because the configuration objects are different, but these codes must comply with
requirements of regulations (show as Table 1.3). If using other command codes, DTU will return “ERR CMD”, for
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