Abstract: A data recorder comprises a DC motor for driving a magnetic tape, a buffer register for temporarily storing input data, a counter adapted to be counted up by a value corresponding to an amount of data stored in the buffer register, a D-A converter connected to the counter and adapted to generate an output signal in accordance with the counted value and control the rotation of the motor, and a decoder for generating an output in accordance with the rotation speed of the motor. The data is read out from the buffer register in response to the output of the decoder and recorded onto the magnetic tape while at the same time the counter is counted down.