PURPOSE: To simplify processing of sentences and words by handling the same characters as the same code in a display unit which displays characters and symbols on its CRT, by adding a character size code to a character code.

CONSTITUTION: This device is equipped with refresh memory 3 stored with characters, control circuit 2 transferring read-out or write information between this memory 3 and electronic computer 1, character generator 5 converting character code signals from memory 3 into character display patterns, and video signal generating circuit converting the output of this generator 5 into a serial video signal. In memory 3 of the circuit in this constitution, character codes and character-code- size codes are stored and character code size control circuit 9 is operated by these codes to control generator 5 so that the character size of the same character will be varied without changing the character code, thereby making it possible to display it on CRT7