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GSM/GPRS/GPS Shield of Futura/Open-electronics

http://www.open-electronics.org/

http://store.open-electronics.org/index.php?route=common/home

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For support use the issues' page on google code:

http://code.google.com/p/gsm-shield-arduino/issues/

or Arduino Forum

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Library created by:

Marco Martines

martines[ dot ]marco[ at ]gmail[ dot ]com
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[1] 	How to switch between Arduino Mega and Arduino Uno?
	
	1)
	Open GSM.h and comment-decomment the appropriate lines like below
	e.g. for Arduino Mega
	//#define UNO
	#define MEGA
	
	2)
	If you use Arduino Uno comment the line in HWSerial.h or decomment if
	you are using Arduino Mega
	e.g. for Arduino Mega
	#define MEGA

	3)
	Save and compile

[2]	How to switch between the old shield (that uses 4 and 5 pins for
	SoftwareSerial and the new (that used 2 and 3 pins)?

	1)
	Open GSM.cpp and comment-decomment the appropriate lines like below
	e.g. for the new one

	//#define _GSM_TXPIN_ 4
	//#define _GSM_RXPIN_ 5
	#define _GSM_TXPIN_ 2
	#define _GSM_RXPIN_ 3
	
	2)
	Save and compile

[3]	My shield doesn't work. Why?
	
	Check this steps and then ask for support on the issues' page on google
	code.

	1) 	SIM900 and SIM908 require about 1 A during the hardest tasks.
		You should have an external power source that can provide about
		1 A at 8-12 V

	2)	If the SIM90X blinks (1 Hz) for some seconds and then turn off,
		probably it's a communication's problem. Check the switch/jumpers
		for Serial communication.

	3)	Arduino Uno has 2 KB of RAM. Library takes about 80% (we are working
		to reduce it), if you use more than 20% left, Arduino can restart
		or print on serial strange strings.