A thermal printer for printing by applying heat energy to a recording medium uses a single logic circuit arrangement to enable operating in a plurality of print modes, and enables easily changing the control logic of each print mode to afford high quality printing. Heating elements apply heat energy to the recording medium. A heating element drive circuit is provided for each heating element to drive a particular heating element. A printing control unit 13 supplies predetermined drive signals to the heating element drive circuits based on pixel printing data input from an external source. The printing control unit 13 comprises a configuration registration unit 36 for storing predetermined value groups corresponding to the drive signal supply patterns so that the value groups can be changed. A logic circuit unit 34 updates the logic operation applied to the pixel printing data according to the value group stored in the configuration registration unit 36, and changes the drive signals to track the supply pattern.