GPRS Shield: Use of GPIOs etc.


I’m interesting in the product ‘GPRS Shield’

Is it possible to write own source code for the GPRS Shield independent from the existing firmware?
In which way can I use the GPIOs?

Thanks for your help.

Kind Regards from Germany


Sorry to tell you that it is impossible to write own firmware and download it into SIM900. All access to SIM900 need to use AT commends by UART of PC or MCU.
GPIOs can be control by AT commands. We have example on wiki: … ield_v0.9b