This program simulates TV static using the X16's bitmap mode.
This program generates a 320x240@4bpp static effect at just over 26 fps. In other words, it generates just shy of 2 million pixels per second, or uses about 4 clock cycles per pixel.
You can check out the source code here: https://github.com/LRFLEW/Noise-X16
Change the PRNG from LCG-based to SWC-based. This provides a better entropy distribution on the screen and is 4 clock cycles faster per frame. The new PRNG has a shorter period, but it is still long enough to run continuously for years without exactly repeated frames.