DIGIPOT stands for Digital Potentiometer. The NS! has an MCP42100 IC that implements four potentiometers (100K). The last of the first three jumper rows shows (in a quite conventinal way) four pots (A to D). There is a firmware (which can be downloaded from the official soundmachines GitHub account) that receives MIDI CC# (from 30 to 33) and translates those to ‘pot positions’.
If you, for example, connect the ‘upper’ terminal of the pot to 5V and the ‘lower’ terminal to 0V, you can pick, at the central terminal, a 0 to 5 V voltage based on the CC#value!
If, on the same central terminal, you connect a 100uF capacitor to ground (keep an eye on polarity) you can implement a variable portamento module driven by MIDI!