Environment sensing/control circuit
AssigneeEMC Corporation
InventorsWilliam A. Brant, Gerald L. Hohenstein
Life of this patent
Estimating the term…
Abstract
An environment sensing/control circuit for use in conjunction with an electronic subsystem. The invention is capable of sensing and controlling conditions of the environment of the subsystem. The invention is capable of being implemented as a stand-alone device or replicated numerous times in an integrated circuit. The invention identifies changes including intermittent changes, in the environment of the subsystem from a reference state, the reference state being dynamically determined by a processor. Upon detecting such a change, the invention signals the processor. The invention can also serve as a flexible interface for control signals from the processor to the subsystem.
Claims36
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of changes to a processor, the environment sensing/control circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- and
- b. an output buffer means coupled to the output of the interrupt memory for providing access to the contents of the interrupt memory by the processor while electrically isolating the output of the interrupt memory from the processor to prevent disturbances or overloading from occurring on the output of the interrupt memory.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of changes to a processor, the environment sensing control circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- b. a reference memory for storing a reference state, the reference state being programmed by the processor;
- c. a difference detector for creating an exception signal when a difference exists between the contents of the reference memory and the environmental condition;
- and
- d. an output buffer means coupled to the output of the reference memory for providing access to the contents of the reference memory by the processor while electrically isolating the output of the reference memory from the processor to prevent disturbances or overloading from occurring on the output of the reference memory.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of changes to a processor, the environment sensing/control circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- b. a reference memory for storing a reference state, the reference state being programmed by the processor;
- c. a difference detector for creating an exception signal when a difference exists between the contents of the reference memory and the environmental condition;
- and
- d. a programmable switching means for preventing the difference detector from making a created exception signal accessible to the processor and from storing the created exception signal in the interrupt memory.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of changes to a processor, the environment sensing/control circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- b. summing means for creating an interrupt signal, the interrupt signal indicating that any one or more of a plurality of environmental conditions has changed;
- c. a reference memory for storing a reference state, the reference state being programmed by the processor;
- and
- d. a difference detector for creating an exception signal when a difference exists between the contents of the reference memory and the environmental condition;
- wherein the output of the summing means is applied to the interrupt memory for determining when the interrupt memory is to store the exception signal created by the difference detector.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of changes to a processor, the environment sensing/control circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- and
- b. a programmable inversion means for selectively inverting the signal representing the environmental condition, the programmable inversion means being coupled to an environmental condition interrupt connection of the environment sensing/control circuit.
An environment sensing/control circuit for receiving a first signal from a processor and transmitting the signal to a subsystem, the environment sensing/control circuit comprising:
- a. a programmable inversion means for inverting the first signal prior to transmission of the first signal to the subsystem;
- b. a control memory means for storing the first signal transmitted from the processor;
- and
- c. an output polarity memory means for storing a second signal received by the environment sensing/control circuit from the processor, the second signal being determinative of whether the programmable inversion means will invert the first signal received by the environment sensing/control circuit from the processor.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of the changes to a processor when used in a sensing mode and for receiving a signal from a processor and transmitting the signal to a subsystem when used in a control mode, the environment/sensing circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- b. a programmable inverter for inverting the signal prior to transmission of the signal to the subsystem;
- and
- c. an output buffer coupled to the output of the interrupt memory for providing access to the contents of the interrupt memory by the processor while electrically isolating the output of the interrupt memory from the processor to prevent disturbances or overloading from occurring on the output of the interrupt memory.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of the changes to a processor when used in a sensing mode and for receiving a signal from a processor and transmitting the signal to a subsystem when used in a control mode, the environment/sensing circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- b. a programmable inverter for inverting the signal prior to transmission of the signal to the subsystem;
- c. a reference memory for storing a reference state, the reference state being programmed by the processor;
- d. a difference detector for creating an exception signal when a difference exists between the contents of the reference memory and the environmental condition;
- and
- e. an output buffer, coupled to the output of the reference memory, for providing access to the contents of the reference memory by the processor while electrically isolating the output of the reference memory from the processor to prevent disturbances or overloading from occurring on the output of the reference memory.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of the changes to a processor when used in a sensing mode and for receiving a signal from a processor and transmitting the signal to a subsystem when used in a control mode, the environment/sensing circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- b. a programmable inverter for inverting the signal prior to transmission of the signal to the subsystem;
- c. a reference memory for storing a reference state, the reference state being programmed by the processor;
- b. a difference detector for creating an exception signal when a difference exists between the contents of the reference memory and the environmental condition;
- and
- c. a programmable switch for preventing the difference detector from making a created exception signal accessible to the processor and from storing the created exception signal in the interrupt memory.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of the changes to a processor when used in a sensing mode and for receiving a signal from a processor and transmitting the signal to a subsystem when used in a control mode, the environment/sensing circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- b. a programmable invertor for inverting the signal prior to transmission of the signal to the subsystem;
- c. a reference memory for storing a reference state, the reference state being programmed by the processor;
- d. a difference detector for creating an exception signal when a difference exists between the contents of the reference memory and the environmental condition;
- and
- e. summing means for creating an interrupt signal, the interrupt signal indicating that any one or more of a plurality of environmental conditions has changed;
- wherein the output of the summing means is applied to the interrupt memory for determining when the interrupt memory is to store the exception signal created by the difference detecting means.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of the changes to a processor when used in a sensing mode and for receiving a signal from a processor and transmitting the signal to a subsystem when used in a control mode, the environment/sensing circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- b. a programmable inverter for inverting the signal prior to transmission of the signal to the subsystem;
- and
- c. a programmable switch for preventing access to the processor of the detected changes in the environmental condition when the access has not been initiated by the processor, and for preventing storage of the detected changes in the interrupt memory.
An environment sensing/control circuit for detecting changes in the environment of an electronic subsystem and transmitting indications of the changes to a processor when used in a sensing mode and for receiving a signal from a processor and transmitting the signal to a subsystem when used in a control mode, the environment/sensing circuit comprising:
- a. an interrupt memory, dedicated to an environmental condition in which changes are to be detected, for storing a flag indicative of detected changes in the environmental condition, the contents of the interrupt memory being accessible to the processor;
- b. a first programmable inverter for inverting the signal prior to transmission of the signal to the subsystem;
- and
- c. a second programmable inverter for selectively inverting the signal representing the environmental condition, the second programmable inverter being coupled to an environmental condition input connection of the environment sensing/control circuit.
A two-mode environment sensing/control system for detecting changes in the environment of an electronic subsystem and transmitting indications of the changes to a processor when used in a sensing mode and for receiving a signal from a processor and storing the signal in the electronic subsystem, the environment sensing/control system comprising:
- a. an environment sensing/control circuit for detecting changes in the environment of the electronic subsystem and transmitting indications of the changes to a processor when used in the sensing mode and for receiving a signal from the processor and transmitting the signal to a subsystem when used in a control mode, the environment sensing/control circuit comprising:
- (1) a single electrical connection means for electrically interfacing the environment sensing/control circuit to a subsystem and conducting a condition signal from the subsystem to the environment sensing/control circuit when the environment sensing/control circuit is used in the sense mode and for conducting a control signal from the environment sensing/control circuit to the subsystem when the environment sensing/control circuit is used in a control mode;
- (2) an output buffer means coupled to the single electrical connection for selectively increasing and decreasing the output impedance at the single electrical connection;
- (3) an interrupt memory means, dedicated to an environmental condition in which changes are to be detected, for storing detected changes in the environmental condition, the contents of the interrupt memory means being accessible to the processor;
- (4) a programmable inversion means for inverting the signal prior to transmission of the signal to the subsystem;
- and
- b. an electronic subsystem coupled to the environment sensing/control circuit via the single electrical connection means for storing the signal received by the environment sensing/control circuit and for transmitting environmental condition signals to the environment sensing/control circuit, the electronic subsystem comprising:
- (1) input memory means for storing the environmental condition signals;
- and
- (2) tri-statable drivers coupled to the outputs of the subsystem for selectively increasing and decreasing the output impedance at subsystem outputs.
Dependencies are inferred from the claim text.