摘要 |
<p>A video computing system is disclosed having an automatically refreshed memory. The computing system includes a dynamic memory connected to a cathode ray tube. A cathode ray tube controller is also connected to the memory and is capable of sequentially generating addresses, corresponding to locations in the memory. A central processor is connected to the dynamic memory and operates on an alternating, two phase fetch and execute cycle. During the fetch phase, the central processor has access to the dynamic memory, while during each execute phase, when computing operations are carried out, access to the dynamic memory is prevented. In contrast, during the execute phase, the cathode ray tube controller is permitted direct access to the memory enabling the video information stored therein to be supplied to the cathode ray tube. The sequential and continuous reading of the memory during each execute phase functions to continually refresh the dynamic memory.</p> |