Abstract: Equipment on automotive vehicle is controlled by a system including at least one semiconductor light sensor having variable sensitivity to light. Each light sensor generates a light signal indicative of the intensity of light incident on the light sensor. Control logic varies the sensitivity of the light sensor and generates equipment control signals based on received light signals. Sensitivity of light sensors may be varied by changing the integration time for producing charge from light incident on light transducers, by selecting between light transducers of different sensitivity within the light sensor, by using a light transducer with a sensitivity that is a function of the amount of incident light, and the like. Controlled equipment includes devices such as automatically dimming rearview mirrors, headlamps, and moisture removal means.

Abstract: Time referenced RF signals are periodically received and processed for updating a microprocessor-controlled clock. The clock automatically scans several frequencies at which the coded RF timing signals are transmitted, selecting the strongest received signal for synchronization therewith and causes a capture LED to be illuminated upon detection of a sufficiently strong signal at the beginning of a minute tone at one of the received frequencies. The microprocessor periodically determines the timing difference between an internal timer and the received RF timing signals. A time difference correction is provided to a digital-to-analog converter which provides an appropriate voltage to a varactor diode in a crystal oscillator circuit for adjusting the microprocessor's operating frequency until it can no longer resolve a difference between the received RF timing signals and its internal timer.