RAMPS 1.3 with Repetier not producing output

I am having a frustrating problem with the electronics on my uncompleted printer. I have RAMPS 1.3 with the Repetier firmware and host controller and ping-ping communication enabled. Whenever I sent manual commands or test gcode to the printer, none of the output pins does anything. I plugged an osciliscope into several of the pins, and nothing happens on any of them.

Any ideas? Do I have bad electronics?

Remove the RAMPS shield from the Arduino, and begin by troubleshooting the communications alone. The RAMPS shield does not have any components involved in communications.

You did not mention if and how you configured the firmware. This would be helpful in order to better assist.

There are forums here for RAMPS, and Repetier. Post in those for better targeted responses.