Patent ID: 7050064

Claim:
A storage medium that stores code for execution by a handheld computing device of the type including a color display having plural lines and display hardware that generates a horizontal line of a color image on said color display during a display interval based at least in part on color mapping data stored in a color memory, said display interval including non-display intervals between line display intervals, said color mapping data encoding a maximum number N of different colors that can typically be displayed on said color display simultaneously, said stored code providing: a first routine that processes at least some user input and controls said display hardware to display colors on the display lines of said display; and a second routine responsive at least in part to said user input accepted and processed by said first routine, said second routine, in use, updating only a portion of said stored color mapping data during any non-display intervals between line display intervals while nevertheless effectively increasing the number of said colors that can be simultaneously displayed on said color display as compared to display where the stored color mapping data is not updated during said display interval, said second routine updating said stored color mapping data such that each color mapping data update applies to plural display lines of said display and colors of said plural display lines are responsive to said plural color updates performed during different non-display intervals between line display intervals, said storage medium further storing information defining said plural display lines that are color-reduced using a closest color color-reduction technique to allow said plural display lines to be color mapped using color updates written for previously-displayed image portions.