Alphanumeric Display Buffer
Original Publication Date: 1985-Mar-01
Included in the Prior Art Database: 2005-Feb-18
Conventional designs for high performance alphanumeric display buffers use either a coded buffer and character generator or an all-points-addressable buffer (APA). Both have disadvantages which are overcome by using a single random-access memory (RAM) which has three data areas. These areas contain a single plane APA, a character generator and a coded buffer. The RAM is controlled by a support module with logic to transfer data between the three areas. When the system requires to update the display, it only has to write to the coded buffer. It then signals to the update logic to translate the new characters into pel (picture element) patterns and transfer these to the APA area.