Configuring UDP in sim300 using GPRS

[yosabath]

sim300 state

hi all,

can anybody send me the configuration setup for initializing the GPRS in UDP protocol? using sim300 modem. i have already initialized GPRS in TCP protocol and sent/received data's. i have already tried to connect the server by changing the protocol and replaced "TCP" as "UDP". In this method i can receive the data from anywhere. whenever i send the data to remote server, the modem replies "SEND OK". but i can't view the sent data in the remote server. i willbe pleased if u give me any solution for the above said problem.

Communication
------------------

AT+CLPORT="UDP","5000"
AT+CIPSTART="UDP","Static IP address","5000"


Reg,

Yos

 

[Derek_Fairbairn]

send ok sim300

I can send UDP data from the SIM300 to a server using the following commands:

AT+CIPSTATUS
STATE: IP INITIAL

OK

AT+CIPSPRT=1

OK

AT+CDNSORIP=0

OK

AT+CIPSRIP=1

OK

AT+CIPHEAD=1

OK

AT+CGDCONT=1,"IP","apn"

OK

AT+CSTT="apn","username","password"

OK

AT+CIICR

OK

AT+CIPSTATUS

STATE: IP GPRSACT

OK

AT+CIFSR

1xx.18.108.49

AT+CIPSTATUS

STATE: IP STATUS

OK

AT+CIPSTART="UDP","2xx.23.12.123","4000"
CONNECT OK

OK

AT+CIPSEND

> Test Message 

SEND OK


The only thing that changes between UDP and TCP is the AT+CIPSTART command.

If you are getting a SEND OK back from the modem it probably means that the modem is sending the data to the GPRS network and it is getting lost somewhere else.
Because UDP is connectionless there won't be any indication that the packet has been lost or dropped.

You should probably check that:
a) Your GPRS network supports UDP traffic. Some operators only allow TCP.
b) Your servers firewall is allowing UDP connections through. Try sending UDP packets from a computer to your server.

To send UDP data to a server you can try this program:
http://sockettest.sourceforge.net/
It allows you to send/receive TCP and UDP data.