Abstract: An electro-thermal actuator has linear displacement of its actuator rod accurately controlled and monitored. The actuator includes a sealed chamber containing an expansible and contractible working fluid. The working fluid is heated by way of pulse width modulated current applied to a heater in thermal contact with the fluid. As heat is applied to the working fluid, it undergoes a phase change to a gas. The resulting gas increases the pressure within the chamber, thereby exerting force on a piston and linearly displacing an actuator rod attached to the piston against the bias of a spring. The actuator includes a temperature sensor mounted within the chamber and in thermal contact with the working fluid to thereby monitor the temperature of the working fluid. The working fluid temperature is provided as an input to a feedback circuit which controls the width of the current pulses applied to the heater used to heat the working fluid.

Abstract: In a communication system for the transmission of messages through a data bus between one or more user microprocessors coupled to the data bus, the user microprocessors having either a serial communications interface (SCI) port or a serial peripheral interface (SPI) port along with a clock port and an input/output port, the user microprocessors being coupled to the data bus by a bus interface integrated circuit, a method to transmit and receive data in a buffered serial peripheral interface (SPI) mode of operation in conjunction with a method of arbitrating data on the data bus.

Abstract: In a communication system for the transmission of messages through a data bus between one or more user microprocessors coupled to the data bus, the user microprocessors having either a serial communications interface (SCI) port or a serial peripheral interface (SPI) port along with a clock port and an input/output port, the user microprocessors being coupled to the data bus by a bus interface integrated circuit, a method to transmit and receive data in an SPI mode of operation in conjunction with a method of arbitrating data on the data bus.

Abstract: The aim of the Chrysler Collision Detector (CCD) Bus System is to allow multiple microprocessors to easily communicate with each other over a common pair of wires (called a bus) using a scheme similar to a telephone party line. All microprocessors connected to the bus are able to receive all messages transmitted on the bus. Any microprocessor with a message to transmit on the bus waits until any current user is finished before attempting to use it. Whenever the bus is available, its use is allocated on a first-come, first serve basis (i.e., whichever microprocessor first begins transmitting its message on the bus after any previous message finishes gets the use of the bus). If, however, multiple microprocessors attempt to begin transmitting their messages on the bus at exactly the same time, then the message with the highest priority wins the use of the bus. All messages have unique message priority values and each message is transmitted by only one microprocessor.

Abstract: Control of a plurality of relay drivers by smart control devices and the continuous status monitoring of a plurality of switches and associated smart sensors, wherein each smart control device and each smart sensor is connected at a separate single point on a single-wire bus, are affected by a smart control and sensor device multiplex system. The system employs a microcomputer and a driver and receiver circuit for developing a particular offset square wave pulse train which is placed on the bus to provide power and control voltage signals to the plurality of smart control devices and smart sensors. The smart control devices contain circuits that respond to the wave form in a manner that causes each smart control device to drive an associated relay driver after a chosen number of polling cycles. Current signals are sent over the bus back to the driver and receiver indicative of the status of the smart control device.

Abstract: A microcomputer controls the energization of both a transformer and display latch driver in a power supply for a vacuum fluorescent display to prevent display flashing at power down. Also provided is the synchronization of the filament voltage to the grid voltage to prevent display pulsations.

Abstract: A method of blocking data transmission from a user microprocessor to a data bus utilizing arbitration and collision detection in a data bus interface integrated circuit utilizing a Serial Communication Interface (SCI) port on the user microprocessor.

Abstract: A bus interface integrated circuit is presented which utilizes an arbitration detector, a collision detector and a contention permitting differential transceiver to work with a serial communication interface port on a microprocessor to determine between contending messages which message gains access to the communication bus by using the value or priority of the ID byte without losing bus time.

Abstract: Continuous status monitoring of a plurality of switches and smart sensors associated with the switches, wherein each sensor is connected to a separate single point on a single-wire bus is affected by a smart sensor multiplex arrangement. The multiplex arrangement employs a microcomputer and a driver and receiver circuit for developing a particular pulse train waveform, which is placed on the bus to provide power and control voltage signals to the plurality of smart sensors. The smart sensors contain circuits that respond to the waveform in a manner that causes each smart sensor to send current signals back over the single wire bus to the driver and receiver circuit and the microcomputer during designated repetitive and sequential time slots. The driver and receiver circuit receives, interprets and converts the current signals into voltage signals used by the microcomputer for establishing a history of the status of the bus, the sensors and the switches.

Abstract: A device to control a temperature variable-resistive type oil fluid level sensor in vehicles. The device employs constant current excitation under control of a relay to maximize the sensor's response and employs a shut-off feature to protect the sensor from overheating.

Abstract: A lamp failure indicating circuit particularly useful for automotive vehicle application such as detecting failure of headlamps, stop lamps and/or turn signal lamps. The disclosed circuit embodiments monitor branch circuits each containing a lamp load and comprising an associated transformer. Each transformer comprises two coils disposed on a ferromagnetic torroidal core. One coil of each transformer is connected in the branch circuit of the associated lamp load, the coil and lamp load being in series, and being associated with a means which forms therewith a complete circuit path which is independent of the power supply which energizes the lamp load. The other coils of the transformers are connected in a circuit to which a test signal is applied with the result of the test indicating whether any of the lamps are failed.