Abstract: An electronic brake controller for controlling electric brakes of a towed vehicle, such as a trailer, wherein the controller includes a resistive braking force sensor that senses the braking force applied by the driver of the towing vehicle to the brake pedal and provides an electrical signal proportional to the braking force to an electronic control unit. The electronic control unit is operable when a microprocessor thereof detects the brake light “on” condition and the presence of the force sensor. The microprocessor receives the signal from the braking force sensor and controls braking force applied to the trailer brakes in proportion to the force applied by the driver of the towing vehicle to the brake pedal. During operation, the microprocessor reads ambient temperature compensated electrical conductance of the braking force sensor to provide a temperature compensated output signal proportional to the braking force to actuate the trailer electric brakes.

Abstract: An exponentially decaying chime sound is generated with a single tri-statable output pin from a microprocessor which is implemented using a single digital output pin line to create states of low, high and disconnect which are input to a control circuit for output to a speaker. Preferably, the control circuit comprises a low pass filter in series with a buffer. Preferably, the buffer is a Darlington transistor. Preferably, the speaker is an electro-mechanical device, alternatively it may be a piezo-resistive device. A method is disclosed for generating a desired audible chime signal with a chime generating circuit regulating a tri-statable output via a single pin of a microprocessor to approximately generate a desired signal frequency, and preferably includes regulating said tri-statable output to produce amplitude decay of the desired signal frequency over time.