Many more details here: http://excamera.com/sphinx/gameduino/

    * video output is 400x300 pixels in 512 colors

        * all color processed internally at 15-bit precision
        * compatible with any standard VGA monitor (800x600 @ 72Hz)
        * background graphics
              o 512x512 pixel character background
              o 256 characters, each with independent 4 color palette
              o pixel-smooth X-Y wraparound scroll
        * foreground graphics
              o each sprite is 16x16 pixels with per-pixel transparency
              o each sprite can use 256, 16 or 4 colors
              o four-way rotate and flip
              o 96 sprites per scan-line, 1536 texels per line
              o pixel-perfect sprite collision detection

    * audio output is a stereo 12-bit frequency synthesizer

        * 16 independent voices 10-4000 Hz
        * per-voice sine wave or white noise