This is a specialty pixel font for 8x8 LED dot matrix displays. Its raison d'etre is to display the time (in 24h HH:MM format) and/or the temperature (with a precision of up to 1 decimal) in an esthetic and optimal manner on four 8x8 displays. Adding two more matrix displays will allow seconds and more decimals to be shown.

The font is proportional, but lacks kerning. The glyphs have one-pixel margins left and right to implement kerning, as it were, with the decimal point. Character spacing (or rather, digit spacing) is therefore 2 pixels.

In order to use the font with ESPHome without rendering issues, I opened the TrueType file with FontForge, added an 8-pixel bitmap (Elements>Bitmap Strikes Available...>Pixel Sizes: 8) and generated the font (File>Generate Fonts...) under a new file name, simasuu_8.ttf.