I had an Apple 2+ back in 1992. It was an old computer, even then.

The Apple 2+ only supported displaying capital letters.

I remember calling a few local BBSes using terminal software that let me press the right arrow (I think) and the character key, and it would display the character inverted (white background, black letter).

Hayes 1200 baud serial modem (I think) hooked up to a serial card.

That's how I knew I was sending a capital letter.

Not sure if it was Kermit though..