Download GR 47/GR 48 Technical Description - conrad

GR47/GR48 TECHNICAL DESCRIPTION
7 TCP/IP stack
An on board IP/TCP/UDP stack has been integrated into
the software negating the need for the customer to
implement one in their own code base.
This is now available through AT commands and the
embedded applications.
7.1
AT command access
Access via the AT commands is detailed in a separate
application note and the breakdown of the commands in
the integrators manual, these are both available on the
extranet.
The way the commands have been structured allows an
application that currently uses SMS/CSD/HSCSD to
immediately switch over to using GPRS with minimal
changes in software. GPRS is on average 1/10th the cost
of these other solutions.
Note!
7.2
The unit is also able to handle circuit switched calls/SMS
while in a GPRS session, this also dealt with in the
application note referred to above.
Embedded application Implementation
There are a number commands allowing various functions,
these are as follows.
• Open/closing IP connection – Negotiates/closes a
dynamic IP address with the server.
•
Send/Receive TCP packets – Performs all TCP
operations to send and receive packets.
•
Send/Receive UDP packets – Performs all UDP
operations to send and receive packets.
•
Resolve URL to an IP address - Similar to nslookup
command in DOS.
•
TCP listen – Enabling the unit to be registered on the
GPRS network and listen for requests from
servers/clients wishing to connect to it.
When the unit is set up and controlled using the
embedded applications either the EA or an external
application can generate data to be sent and can pass it to
the module for transmission.
LZT 123 8081 R1C
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