Hello and welcome to Tonc, a guide to GBA programming. In these pages you'll find information on various aspects of GBA programming, such as the GBA video system (including a detailed, mathematically correct look into how the GBA does those rotational sprites and backgrounds), button handling and DMA, but also trickier subjects like interrupts, BIOS calls, and graphical tricks like blending, windowing and Mode 7. All subjects have at least one non-trivial demo for them.