VIDEO ATTRIBUTES DECODER FOR COLOR OR MONOCHROME DISPLAY IN VIDEOTEX MODE OR HIGH DEFINITION ALPHANUMERIC MODE.

摘要

P THE PRESENT INVENTION CONCERNS A VIDEO ATTRIBUTES DECODER FOR COLOR OR MONOCHROME DISPLAY IN HIGH DEFINITION ALPHANUMERIC MODE OR IN VIDEOTEX MODE WITH IN THE VIDEOTEX MODE THE CHOICE BETWEEN THE ALPHANUMERIC MODE OR THE SEMI-GRAPHIC MODE, INCLUDING A DIGITAL CIRCUIT 'CLOCK 25, A CONFIGURATION REGISTER 23, A LINE ATTRIBUTES REGISTER 32, 33, A ATTRIBUTES DECODING CIRCUIT21 CONNECTED TO THESE DIFFERENT REGISTERS, A CHARACTER MARKING CIRCUIT41, CONNECTED TO THIS MASKING CIRCUIT41 AND THE CIRCUIT CLOCK25, A BACKGROUND INVERSION CIRCUIT53, A CHARACTER COLOR CONTROL CIRCUIT51 AND A BACKGROUND COLOR CONTROL CIRCUIT52, THESE LAST 3 CIRCUITS CONNECTED INTO THE OUTPUT DECODER CIRCUIT OF THE MULTIPLEX CIRCUIT50 AND CONTROL OF THE MONITOR GUNS, CHARACTERIZED IN THAT THE OUTPUT402 OF THE SERIALIZER CIRCUIT40 IS SENT ON A CIRCUIT54 OF ENLARGEMENT OF THE POINT OF WHICH THE OUTPUT542 IS CONNECTED TO A ENTRY OF THE DEMULTIPLEXING CIRCUIT, AND IN THAT IT ALSO INCLUDES A DOUBLE HEIGHT LOGIC CIRCUIT31 CONNECTED ON THE ONE HAND TO THE LIST OF ATTRIBUTES OF LINES33 AND ON THE OTHER HAND TO THE SELECTION LINESLC0, LC3 OF A CHARACTER IN A DEAD MEMORY15 GENERATOR OF CHARACTER. /P