SIM900A; GPRS Static IP; MCU - Page 1
Forum section: electronics / beginners

author: A2
author_rank: Contributor
timestamp: August 14, 2014, 01:48:30 pm
content: I have a complete SIM900A module.I am able to send sms over it.But now I want to send data using GPRS over static IP address.I don't know how to proceed. Any example code.IP address, do i need to have internet plan on SIM card or what?Any example code?I have to interface with microcontroller with uart , Rx,tx & Gnd

author: Wilksey
author_rank: Super Contributor
timestamp: August 14, 2014, 02:18:33 pm
content: To keep it brief,You will need a SIM which is data enabled, it doesn't necessarily need a data plan, but it might get expensive without one, will also work on PAYG SIMs, just check the tariffs.You will need 3 pieces of information:1. the APN (Access Point Name)2. the username3. the password4. the dial up number.For example, if you are on Vodafone in the UK the APN will be something like "internet" or "web", and the username and password might be the same ( "web" and "web") for example, this is freely published for most providers on the internet.The dial up number is usually almost always the same: *99#, it is worth checking though as some state it as *99*1# for example.You will also need to read the TCP/IP AN for the SIM900:http://www.propox.com/download/docs/SIM900_Application_Note.pdfHope this helps!

author: A2
author_rank: Contributor
timestamp: August 15, 2014, 01:38:20 pm
content: I have got one static address. But I have some confusion:1. I was reading this, & on post#3, someone has posted code:http://www.edaboard.com/thread219547.html.2. Now I have one Sim900A module with SIM with data plan & a static ip address.3. What to do now, I make my sim900a module client & keep on sending data on that static ip addressi.e on client side:AT+CIPSTART=”TCP”,”188.33.176.204”,”8080”The ip space abobe I have to put my static ip address.4. Now what will happen? data sent over address will go to that ip adress i.e server & there I have to write some code which extract data from that staic ip address & finally store in computer.Is that whta will happen

author: Wilksey
author_rank: Super Contributor
timestamp: August 15, 2014, 03:23:17 pm
content: Ok,Once you have established connection, i.e., you have your connection and the IP address has been assigned as you would expect and you are on the mobile network etc, you have two options.1.) Use a built in protocol, I can't remember specifically but some GPRS/3G modules have stuff like FTP, HTTP etc already built into them, so you don't have to do the conversion.2.) Open a RAW socket and send data, much like you have described, so you open a TCP port on host xxx.xxx.xxx.xxx, say 8080. Your machine will have a listening socket, whether that be through another SIM900 or a windows / linux based machine connected to a broadband line etc, you then just send data to it, much like you would send data to a screen or serial port.The application notes should have some examples.

author: A2
author_rank: Contributor
timestamp: August 18, 2014, 12:55:55 pm
content: What I have done is:1. On receiver side I have PC whose IP address I had checked from:http://www.whatismyip.com/2. On transmitter side I have sim900A module with microcontoller.From Sim900A module I have send data on IP address noted from 1, but I don't know how to check data on receiver side.What shoudl I do or I am doing it all wrong

author: Wilksey
author_rank: Super Contributor
timestamp: August 18, 2014, 03:51:27 pm
content: In the application notes there is a section on being a TCP client (3.1.1 Page, which I guess is essentially what you are after?It indicates that after a AT+CIPSEND, it asks for the data to send with a ">" prompt, terminated with a CRLF.Then the socket stays open until the receiver terminates the connection, whatever is being sent back should be written to the serial port of the SIM module (where your MCU UART is).