DISPLAY DRIVER WITH BUILT-IN RAM, AND PICTURE DISPLAY DEVICE MOUNTED WITH THE SAME

摘要

PROBLEM TO BE SOLVED: To realize display control such as easy and flexible scrolling of a display screen without increasing a load of a CPU. SOLUTION: This picture display device comprises a latch shift register 14 which receives display data read from RAM 12, shifts the read display data according to the directions of scrolling in the case of scrolling a display screen 20 in the horizontal direction, and holds the read display data in the case of scrolling the display picture 20 in the vertical direction; and comprises an access control circuit 15 which reads the display data from the RAM 12, rewrites the display data shifted from the latch shift register in the original position of the RAM in the case of scrolling the display screen 20 in the horizontal direction, and rewrites the display data held in the latch shift register in the position shifted by the scrolled amount from the original position of the RAM in the case of scrolling the display screen 20 in the vertical direction.