3G modem in USB host interface

Hi All,

I am want to connect Reliance usb modem with Sakura board. Anyone has idea, will it work, will modem get spoiled because of it?

Please share the code if you have anything related to it and idea regarding the same.


Thanks and Regards,

Ashok Kumar Ponnaiah

  • How are you doing this ?

    Are you connecting via USB ?

    via Wifi ?

    via Ethernet ?

    Please give a little more info ...

  • via USB

    SAKURA will be usb host device.

  • If you want to use GR-Sakura board as USB host, you need host side drivers for serial port of the usb modem you are going to connect. This will require lot of memory and the wrapper may to difficult to implement. One simple solution may be directly accessing the TTL serial pins in the modem using Renesas's UART peripheral. The modem's manufacturer may(not reliance) provide you the datasheet of commands. I am not sure if the usb host is capable to communicating directly with the modem. HID devices like pendrive may be easier to implement. Correct me if I am worng.

  • @  embeddedmcu

    u have to interface with USB Host...

    @Bharathi interfacing with serial communication will be low speed.....................

  • To connect to the internet you must have or establish a PPP connection.

    You can then use  Sockets programming  or any high-level component (HTTP Client, NTP Client).

  • Hey, Bharathi was correct. If you want to use a 3g USB modem, You need to interface with the USB Host.

    And doing this will be very very very very very very very very very very very very difficult. I can't even think of doing it.

    Generally you'd use drivers - but these drivers are only for windows or ubuntu, and nobody writes drivers for microcontrollers as they are waay too complicated. The first thing mentioned - interfacing with usb-host is basically you writing a driver for Sakura with the Modem.

    So, basically ... I'd recommend you find another way of communicating ... Ethernet for example.

  • Sockets programming  or any high-level component (HTTP Client, NTP Client) ....will be good

  • if you have something like this usb modem dx.com/.../usb-tri-band-gprs-modem-cell-phone-radio-gsm-900-1800-1900mhz-12057

    then you can hack this circuit and take out input from USB to UART converter that is tx and Rx....

  • @Ravi : Even if RX-TX communication is possible, the protocols for TCP/IP and so on will still be difficult to handle.

    The problem isn't the communication, It's the protocol used in communication. Drivers are generally used to figure out which byte sent by the modem is for what (it changes from modem to modem) And understanding that protocol is quite complicated.

    The RX-TX Modems will still use TCP IP and send each byte ... including the sync, start etc via UART.

  • Based on all of your views and amount of difficultyin this case. i want to try other mode of wireless connections.

    Is nordic & cc2500 wireless is supported in sakura lib. how to use the same.

    Thanks and Regards,