PSG command argument sets the zero adjust potentiometer of the ADEPT card. Only values between 1 and 255 are accepted. The setting is stored in non-volatile memory on the ADEPT board. This is one of the settings that are automatically picked during both long and short auto calibration. Please refer the calibration section for its usage.

The settings set with this command can also be done with PZ commands. One does not have an advantage over another; usage is left to user preference.

On the Tunable Lens card, this command gets and sets a different parameter. Tunable lens diopter changes with temperature, this change varies with current being applied to the lens. So we built a model equation to help us calculate Diopter per Celsius change as a function of current. PSG command sets the reference temperature in this model equation. More info here