PURPOSE: To perform dot plotting at a high speed by decoding a part of data from a CPU so that bit mask information may be outputted, decoding the rest of the data so that write information may be outputted and writing the data in plural display memories.
CONSTITUTION: A part of and the rest of information from the CPU 10 are processed by decoders 30 and 31 respectively, and the bit mask information and the write information are outputted from the decoders 30 and 31 respectively. The information is supplied to write control circuits 40 to perform the write in the display memories for R, G and B 51-53. Therefore, the dot plotting is performed by accessing the memory once and a program for setting a color register is not necessitated, thereby performing the dot plotting at a high speed.
FUJIGAMI YOSHIHIRO
KOHIYAMA TOMOHISA
KITATSUME YOSHIAKI
NITTA HIROYUKI
