How about a 12bit DAC outputting 0-23. 59 volts to a working DMM ![Cheesy :D](https://www.eevblog.com/forum/Smileys/default/xcheesy.gif.pagespeed.ic.KPzuH4J-TG.png)
I recall seeing someone do that already with an arduino or some such, posted the video on youtube of their wonder-creation, than apologized when it's clear that it doesn't actually show accurate time due to using an 8 bit DAC ( or was it 10 bit ? I don't remember) and rounding errors in their math software, and drift and temperature instabilities, etc.