Horizontal Scrolling by Pel on a CRT Display System
Original Publication Date: 1984-Jun-01
Included in the Prior Art Database: 2005-Feb-04
This circuit provides means to effect horizontal scrolling in a CRT display by one or more pels to provide a smooth scrolling effect. It can be used in conjunction with a system which scrolls by a character at a time to provide intermediate scrolling between character shifts. Character or graphics dot patterns are, as normal, applied in parallel to a shift register 3. The serial output stream is fed to a further shift register 4 which is clocked at the same rate as shift register 3. An output from each stage of shift register 4 is connected to an input of a multiplexer 5. In accordance with input signals applied to position inputs 0, 1 and 2, the multiplexer connects a selected one of its inputs to a video output line.