A gas-based regulatory apparatus has an electrical input, optionally connected to an analog to digital converter; a central processing unit (CPU) comprising a non-volatile memory for storing and retrieving program and configuration data and a random access memory for storing and retrieving other data; a visible alphanumeric display means connected thereto; a user input means adjacent to the display and connected to the processing means; an alarm driven directly or indirectly from the CPU; a pneumatic valve having an input port and an output port, and being driven directly or indirectly from the CPU; and a program that runs on the CPU, for receiving user input, measuring input voltages and pressure voltages from the analog to digital converter, displaying data, converting measured voltages to gas and pressure units, implementing a control algorithm, and driving the pneumatic valve and alarm.