I 'm planning to control a DC motor via certain signals. Motor requires 9 V, 700 mA of voltage approximately. The voltage will be provided by a Ni-Cd battery. However, the signals that are responsible for the control of the motor are the output of a BeagleBoard-xM (1.8 V, 20 mA approximately).
How can I combine the signals with the battery voltage in the circuit I have to construct? I am a begginer in electrical engineering and any suggestion would be appreciated.