Geeetech

Hi!

I have Arduino UNO R3, Catalex Catduino (arduino compatible board http://item.taobao.com/item.htm?spm=a1z ... 0548359578)
Also I have Arduino GPRS Shield.

With Arduino Uno R3 that GPRS Shield works properly. But when I use Catduino, GPRS Shield turn-off.
For example when I send SMS message GPRS immediatly turn-off.

What can be cause of that problem?

I bought AC to DC adapter 12V/1A and with that equipment Arduino GPRS Shield and Catduino works properly.

CATduino may not compatible with GPRS module。and GPRS sheild worked at 9V

I have one case: Catduino and GPRS Shield applied to computer by USB then GPRS Shield switches off when it send SMS. And other case, when Catduino and GPRS Shield applied to 12V/1A AC/DC adapter and work properly. May be it is not enought current in first case?

Note:USB port is worked 5V. the power consumption is very low.