Low-cost display controller comprising a DMA or communications controller operating under processor control

摘要

A DMA or communications controller, such as a DMA serial controller, operating under control of, and in cooperation with, a microprocessor together perform the functions of, and hence replace, a bit-mapped display controller, thereby avoiding the cost of the display controller. The microprocessor is programmed to cause the DMA or communications controller to transfer image data to a display, like the display controller. Under the processor's repeated commands, the communications controller transfers data representative of an image from a memory to the display a line of a frame of the image at a time. The processor generates control signals, such as horizontal and vertical sync signals, to cause the display to display the image represented by the transferred data.