In Raster Mode, the image buffers can reside in the MCUs internal SRAM, or in the external memory connected via the EPI. The image buffer contains a space for the Color Palette data and Image Data. The LCD DMA Engine copies color palette data to the LCD module’s internal color palette RAM. The LCD DMA engine sends image data to the main LCD controller’s image data FIFO. The LCD DMA engine and Raster controller will continuously retrieve more image data from the SRAM Frame Buffer and use it to refresh the display. The image data path is active constantly once Raster Mode has been configured and enabled. This means that the display will be continuously refreshed with data from the frame buffer. The CPU can still write to the frame buffer while this is happening, and the display will be updated with the new image data on the next refresh. Both DMA only and Ping-Pong modes are allowed so that the images can be dynamically updated. The output of the Raster Block is tailored to controller-less LCD screens, and consists of standard RGB data lines and control signals.