
Old Chips, New Glitches: the CGA/CRTC "Phantom" VSync
A dive into an obscure hardware glitch in the 6845 CRTC chip, which has to do with register rewriting, and only seems to really have a noticeable effect on IBM CGA boards (so far). Let's see what it is, why it occurs, and how to avoid it. There's bonus fractals, too!