Arduino GSM Shield and Sparkfun SD Card Reader

Projects General Guidance
1

Hello,
I'm working on a project where I use the Arduino GSM Shield and a Sparkfun Micro-SD Card reader.
Both work perfectly in separate sketches.

I'm using an Arduino Mega

However when I use them in one sketch, as soon as I access the SD Card, the GSM Shield shuts down.

I don't really understand since I don't see any Pin conflict.

The SD-Card reader use the SPI interface on Mega pins 50-51-52-53

The GSM shield uses Pin 2,3,7 and 10

I had a look into the GSM library itself and did not find any reference to the SPI libraries, which the SD card does use.

Any idea, what this could be and how I can fix it.

Thanks

Patrick

2

I believe the SD-lib uses pin 10 as an OUTPUT, check code