Abstract: A temperature compensation injector control system as used in an electronic fuel injection system for motor vehicles utilizes the value of the voltage levels across the coil (18) to determine the coil's (18) temperature. A multiplexer (20) responds to the value of the source of power (14) and the voltage drop across the coil (18) created by a small leakage current to generate digital signals to a microprocessor (10) for modifying injector control signals.

Abstract: A method of measuring barometric pressure with a manifold pressure sensor (62) in a microprocessor based engine control system utilizes known engine operating conditions to interrogate the sensor. Also on engine turn-off, a power latch signal (158) is generated to delay power removal until the throttle valve (160) is driven open and the pressure sensor (62) is interrogated for its value. This value at this time is the ambient or barometric value of pressure. This value is stored in the microprocessor's (26, 28) memory (84, 86) and maintained by means of a standby voltage (80). During engine operation, the pressure sensor (62) is interrogated and value of the stored barometric pressure is changed by one unit of pressure if the stored and measured values are unequal.

Abstract: A dual microprocessor computing system is used to control an engine in a motor vehicle. Each system contains a Personality Programmable Read Only Memory (PPROM) containing system calibration data that is transferred from the PPROM to the read-write memories in the microprocessors. In order to identify each PPROM a byte of memory contains a check sum and a byte of the microprocessor memory contains an identical check sum. During data transfer, the check sums are compared. Also during data transfer, the amount of data being transferred within a predetermined interval is counted both at the transmitter and the receiver memories.

Abstract: A microprocessor based engine control system for controlling heavy engine loads responds to a heavy load control signal (38), and manifold pressure (62), throttle blade position (34) and engine speed (74) signals from various sensors. All of this information is combined with engine control data from a Personality Programmable Read Only Memory (44) in a microprocessor (26) to generate an actuation signal to a delay means (132). The delay operates to hold the heavy load disconnected for a period of time to allow the engine to operate to increase its engine speed. After the delay or in those instances that the speed is great enough, the actuation signal operates a clutch (54) to connect the heavy load to the engine.

Abstract: A multiprocessing microprocessor based engine control system for an internal combustion engine controls the amount of fuel supplied to the engine. The various input-output devices used in engine operation, transmission control 20, spark advance control 22, etc., are controlled by dual microprocessors 26, 28 connected in parallel for partitioning and sharing of the various engine control functions.

Abstract: A fuel control system for actuating injection means for controlling small fuel flows is described in a microprocessor based engine control system. The short time duration fuel pulses are sensed and the control system processes the skipping of the injection pulses in the opposite direction of cylinder ignition or precesses skipping around the engine. In one example, in every three fuel pulses, one is omitted and the remaining two are increased in time duration. This processing of the fuel pulses allows each cylinder to omit receiving fuel only once in four engine cycles for a four cylinder engine. Other counts may be used providing that the count is not a multiple of a factor of the total number of cylinders. The increased time duration of the fuel pulses allows actuation of the injector in its linear region of operation.

Abstract: An extended range throttle body fuel injection system wherein overlapping or near-overlapping fuel quantity pulse width signals are compensated to maintain the operation of the injectors in a near linear operating mode. The system is capable of being implemented in software for controlling microprocessors in a microprocessor based system or in hardware logic for operation in a hardware system.

Abstract: A linear variable phase transformer directly converts mechanical displacement information to phase information capable of varying fully over preferably more than a 120.degree. period of a typical AC cycle and up to 360.degree. or more phase variation. Three or more linearly arranged primary windings produce respective AC magnetic fluxes that are phase separated by equal amounts over such full period. A core, which is movably positioned relative to the primary windings, receives and/or combines one or more of such fluxes to produce an output flux that induces in a secondary winding an output AC electrical signal having a phase corresponding to that of the output flux and, thus, the positional relationship of the core and the primary windings. The output AC electrical signal is a time-based signal that can be utilized directly in analog applications or readily demodulated for digital use.

Abstract: A linear variable phase transformer position to phase transducer produces a linear phase change in an output signal with respect to displacement. Moreover, the magnitude of such output signal remains relatively constant while such displacement occurs. The transducer includes two primaries which are specially wound according to sine and cosine functions and are excited out of phase, a secondary, and a core that combines the primary signals and induces the output signal in the secondary according to the core position relative to the primaries.

Abstract: A pulse width modulator digital servo system combines a digital feedback signal, which is developed in response to a time based signal directly indicative of a positional physical parameter of a servo actuator, and a digital command signal, which is indicative of a desired position of the servo actuator, to produce a digital resultant signal. A pulse width modulator produces a control signal output that is pulse width modulated in accordance with the digital value of the resultant signal to control operation of the servo actuator to achieve the positional relationship commanded. The pulse width modulated control signal is balanced when the combined resultant signal has a predetermined or constant value and is unbalanced in respective directions depending on whether the combined resultant signal is larger or smaller than such predetermined value.

Abstract: A linear variable phase transformer directly converts displacement to phase information. In one form the relationship of such displacement and such phase information is substantially linear or directly proportional. Moreover, a circuit is provided for directly converting such phase information to digital information which is preferably provided in a binary format.