Make your OWN 8-bit Function Generator - R-2R Ladders and DACs

Nowadays, most electronic gadgets have at least some sort of digital controller. But a lot of those same gadgets have analog outputs in forms such as audio. How do they manage to take their binary 1's and 0's and turn them into the analog values they produce?

-- Links --
Schematic: https://sinelab.net/img/r2r_ladder_schematic.png
AVR Code: https://sinelab.net/code/r2r_ladder/main.c
PC Code: https://sinelab.net/code/r2r_ladder/sine.c
My Website: https://sinelab.net
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