PURPOSE: To simplify a process adjustment (horizontal amplitude, horizontal screen position, vertical amplitude, vertical screen position, etc.) of the multi- mode type CRT display monitor which varies the deflection frequency following up a horizontal and a vertical synchronism polarity.

CONSTITUTION: The process adjustment of the CRT display monitor consists of the multi-mode type CRT display monitor consisting of (1) a nonvolatile memory 33 stored with adjustment data of plural modes, (2) a read setting circuit 35 which selects one of the adjustment data of the modes and sets its value in a DAC, (3) a synchronism polarity detecting circuit 1 which decides the polarities of a horizontal and a vertical synchronizing signal, (4) a DAC circuit 34 which converts the adjustment data into a direct current, and (5) an analog output circuit 4 which controls the horizontal amplitude and horizontal screen position, and vertical amplitude and vertical screen position of the CRT display monitor by using the adjustment data converted into the direct current, an image position and amplitude detector 8 which detects a CRT image, and an automatic adjuster 9.