A timing device includes an oven having a chamber, a crystal oscillator disposed in the chamber that generates a clock signal, and one or more sensors to generate operational characteristic signals indicative of respective operational characteristics of the crystal oscillator or the oven. The timing device includes a plurality of I/O connections and an IC device. The IC device includes processing logic to generate information that indicates how the generated clock signal is to be modified and a modulator coupled to the processing logic and the crystal oscillator. The modulator modulates the generated clock signal in relation to the information to generate a modulated clock signal indicative of the one or more operational characteristics of the crystal oscillator or the oven. The modulator outputs the modulated clock signal over a single one of the plurality of I/O connections.