Video memory unit

Abstract

Abstract PURPOSE: To perform write-in and readout of the video memory in high speed and with a simple circuit constitution, by locating the memory card so that the card address is different each other and reading out the data output and outputting it to the data bus with the readoud data register. CONSTITUTION: The AND circuit 20 receives the signal of the card address bus 200 and generates the card selection signal with the card address signal corresponded. Further, the memory 10 memorizes the output signal 204 of the write-in data register to the address designated with the signal 201 of the address bus and sets the memory data designated and read out with the address signal of the memory 10 with the readout data set signal 104 of the control bus 206. Then, the memory cards are located so that the card address is different each other, and the readout data reigster 12 outputs the data output to the readout data bus. Accordingly, the write-in and readout of the video memory can be made with a simple circuit constitution and in high speed. COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Takeshi Arakawa

Bibliographic Details