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GPRS Shield (SKU: SLD01098P)

← Seeed Products' FAQ
  1. How to modify Code for leonardo 

  2. Using GPRS Shield v2 with Mega 

  3. Baud Rate of GPRS shield 

  4. Power on GPRS shield from software    

  5. Update the firmware of SIM900
    Please download the firmware "SIM_900_AGPS_instructions" from Resource module on the wiki,if you have any problem of software or hardware.And this latest one can support HTTPS ,etc.More information please refer to the introduction within. 

  6. RTC of GPRS shield
    The specification of SIM900 says it has a RTC backup,but we have not used it so far. Maybe you can refer to the manual and make a demo yourself or we would make it in the future.

  7. I can't send or receive any SMS with this GPRS shield.
    a. Please make sure that the SIM card is well inserted 
    b. Check the card on the phone whether it works.
    c. Try to upload the test code from our wiki and send AT commands to see whether any good returns.
    d. Try to change the "#define _SS_MAX_RX_BUFF 64 // RX buffer size" in "libraries\SoftwareSerial\SoftwareSeriall.h" to "#define _SS_MAX_RX_BUFF 128 // RX buffer size
      8.  Two alternative ways to help to wake up the GPRS shield: 
           (1) Pull DTR pin low : The serial port will be active after DTR is pulled to low for 20ms
           (2) RTC alarm expires 
     
                                                                                                                Contributed by Israel Gimel from product comments

      9. Which type of SIM cards work with GPRS Shield?
           SIM900 used in GPRS Shield supports 850/900/1800/1900MHz GSM bands.



Please visit our wiki page for more info about this product. It will be appreciated if you can help us improve the documents, add more demo code or tutorials. For technical support, please post your questions to our forum.

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