help regarding imlepmentation of TCP/IP stack in pic controller(PIC18f4550)

[zeeshan ahmed]

Hi all...
i m working on a project, in which i will transmit sensor's outputs over internet using gprs modem.....right now i m facing problem regarding implementing TCP/IP stack in PIC controller...
Any help or supporting material in this regard will be highly appreciated.
Thanks

 

[FvM]

Ideally, you would want to use a GPRS modem with built-in TCP stack, e.g. SIM300. Otherwise, you have to implement TCP and PPP protocol, including authentication and similar stuff. Quite demanding for a PIC18. You'll find example codes e.g. from Microchip or CCS, if you want to go this way.

 

[zeeshan ahmed]

thanks for yur reply
yes i m using a GPRS USB modem.....it means that i dnt have to write TCP/IP stack in my case ??
then plz help me how can i initialize MODEM for GPRS communication....and how to send data to my home made server which have particular IP....the goal of project is to transmit the readings of sensors connected to PIC18f4550 controller over internet using GPRS modem...

Thanks for your time!!!

 

[FvM]

yes i m using a GPRS USB modem

The modem must have a serial interface to connect to the PIC processor. USB isn't an option.

how can i initialize MODEM for GPRS communication

You have to consult the AT command manual of your modem. GPRS related commands are more or less standarized, but TCP/IP commands, if supported by your modem, are vendor specific. What's the exact modem type?

 

[zeeshan ahmed]

thanks for your reply...
1) Actually i will use a USB host controller IC for interfacing USB GPRS MODEM to PIC controller...

2) i m using a similar EDGE GPRS USB modem (GPRS/EDGE Wireless Modem (U901) - China Edge Wireless Modem, Edge Modem, Edge Usb Modem in Modem). The vendor and manufacturer of USB modem which i m using is unknown.

 

[FvM]

I won't expect a TCP/IP command set for the said modem, because it's mainly intended as a PC peripheral. I also don't see the benefit of using a (possibly cheap) PC modem, if it enforces the usage of an USB host controller. Most people are using dedicated embedded GSM modems with microcontrollers, e.g. said SIM300.

If my assumption about lack of a TCP/IP stack is correct, you're back to the TCP/IP stacks mentioned in my first post.