Thank you. I just had an epiphany. In elementary school computer lab, we'd all fight for the color machines. There were two of those and like 25 of the green screens.

I remember wondering how the game "knew" what kind of screen it was on. How did it change from a solid color (for the lucky kids) to a pattern (for the rest of us)?? I just shrugged it off as the computer knowing the display type from the connection.

Those two images in your link made it all just click right now, 30 years later.