thanks in advance!
the problem: Have a IMu 9 degree of freedom board from sparkfun LSM9DS1
and a Arduino micro with an xbee and a 9v batt.
serial data does not work when I have the cricuit power with a battery ( also have a 5 volt voltage regulator power the arduino )
if I use the usb port the serial data works ( GREEN led on TX blinks )
I have tried to use also an UNO and have the same issue.
any advice please.