Comment by reaperducer
3 years ago
The smallest I ever did was 4x8 on a Commodore 64. The actual text was 3x7, with a one pixel spacer on the right and bottom. Did this for a terminal emulator that output 80x24 text (plus a status line) on the 320x200 screen.
Rending was slow, but that's OK because 1200 baud was state of the art at the time, and the computer could keep up OK. 2400 baud worked, if there wasn't too much scrolling.
Eventually we came up with a way of doing a 8x8 characters on a 640x200 screen using some of the scrolling methods we saw from the demo scene, but it was blurry, even on a good monitor, and we couldn't output the characters fast enough to be usable. By then the 128 was out, and it was assumed people who wanted 80 columns would just use that machine's real 80-column mode.
I think I remember seeing 4x6 (3x5) on the C64, possibly in an environment like GEOS. That’s about the limit of what is usable, pixelation-wise.
Edit: The smaller GEOS UI font indeed had a cap height of 5 pixels, but it was variable-width: https://upload.wikimedia.org/wikipedia/en/e/e2/GeOS_Commodor... (the font of the icon labels)
Tasword 2 (word processor) on the Spectrum did 4x8 (3x7 with a spacer) to get 64 characters per line which was miraculous at the time.
(They probably kept it on an 8-high grid because the Spectrum's screen layout was a bit bonkers if you went off 8-alignment.)