摘要 |
A display apparatus is disclosed comprising a picture memory having memorizing portions which correspond in one-to-one relation to characters or graphics to be displayed on the screen of a cathode ray tube display monitor, a CPU of a controller for reading or writing the picture memory, and a CRT controller for generating timing signals which are used for displaying on the screen of the cathode ray tube display monitor. Data are read from the picture memory by the timing signals which the CRT controller generates and displayed on the cathode ray tube display monitor, wherein the frequency of operation clock signals of the CPU in the period in which the picture memory is read or written and that in the period in which the picture memory is neither read nor written are made different, so that the CPU can operate at high speed. |