The SMST Auto/Manual Station can display a process variable input (square root function is available) and provide a remote (e.g. controller) set point (for SMST-111) or manipulated-value output (e.g. to a valve actuator) (for SMST-121). In Auto (Cascade: C) mode, the output corresponds to a cascade input or DDC signal from a supervisory computer; in Manual (M) mode, the output corresponds to a manual set point. Made may be changed by C/M switches on the front panel, or by a status input signal, and mode output signals are provided. In manual (M) mode, the output is adjusted using (up/down) press switches on the front panel of the SMST-111, or using a lever on the front panel of the SMST-121.