Hi all,
We are connecting two arduino uno with raspberry pi through usb connection. sending the string data to the arduinos. The Stepper motor is not running from the arduino when the data received. But,when we connected the raspberry pi with monitor(computer monitor) through hdmi cable,it runs the motor correclty according to the pulses. And also without connecting the hdmi cable,when pressing the arduino side cable,it works correctly. What may be the problem????? We have connected the arduinos with seperate 12v batteries. The arduino gets interrupts from raspberry pi.Kindly,help.
I recommend that you show code and wiring diagram with this post. Probably improve your chances to get help.