Definitions

 

Acknowledge:  A reply message used to indicate that a command or trigger message was received.

Actuator: An actuator is a transducer that accepts a data sample or samples and converts them into an action. The action may be completely contained within the TIM or may change something outside of the TIM.

Address: A character or group of characters that identifies a register, a particular part of storage, or some other data source or destination.

AddressGroup: A collection of TransducerChannels that respond to a single address.

Alias: An alias is an alternate designation for an object. Throughout this standard, it is a number used in place of the eighty-bit UUID when addressing a TIM.

Buffer: An intermediate data storage location used to compensate for the difference in rate of flow of data or time of occurrence of events when transmitting information from one device to another.

Controller: A device, possibly an NCAP, which acts as the master to control all of the devices on a transducer network.

Calibration: The process used to determine the information that must reside in the Calibration TEDS to support correction.

CommunicationsChannel: For the purposes of this standard, a CommunicationsChannel shall be defined as a communications path between the NCAP and the TIM. A CommunicationsChannel may be used for data communications and other functions as well as controlling the operation of a TIM. All TIMs and NCAPs must have at least one CommunicationsChannel.

ControlGroup: ControlGroups are manufacturer specifications that define the inherent relationships between the TransducerChannels of a multi-channel TIM. This ControlGrouping information is not normally used by the TIM itself. This information is used to identify TransducerChannels that are used to control some characteristic of another TransducerChannel. For example, a ControlGroup could be used to identify an actuator that is used to set the threshold of an analog event sensor.

Logical CommunicationsChannel: The term “logical CommunicationsChannel “ is used to denote a CommunicationsChannel when the logical properties are what are under consideration rather than the physical properties. If the term CommunicationsChannel is used without the modifier, the logical CommunicationsChannel is what is under consideration.

Physical CommunicationsChannel: The term “physical CommunicationsChannel “ is used to denote a ComunicationsChannel when the physical properties are what are under consideration.

Correction: The evaluation of a multinomial function using information from the calibration TEDS together with data from one or more transducers.

Data conversion: Data conversion is the translation of data from one numeric form into another (e.g. converting a scaled integer to a floating point number during correction).

Data model: The data model is the numeric format in which the TIM shall output or accept data.

Data-set: The collection of samples acquired by a sensor (or applied by an actuator) in response to a trigger command.

Data sheet: A set of information on a device that defines the parameters of operation and conditions of usage (usually produced by the device's manufacturer).

Data structure: A group of digital data fields organized in some logical order for some specific purpose. A two-dimensional paper version of a data structure is an empty fill-in-the-blanks form or an empty tabular chart with organized column and row headings. A data structure is the template by which data is stored in computer memory.

Digital interface: A communications media and a protocol for transferring information by binary means only.

Electronic data sheet: A data sheet stored in some form of electrically readable memory (as opposed to a piece of paper).

Embedded transducer: A device that behaves as a transducer from the point of view of the controller even though nothing outside of the TIM is sensed or changed. Embedded transducers are useful for setting or reading operating parameters of other transducers.

Enumeration: The assignment of a numeric value to a specific meaning within the context of a specific data field. Binary numbers are usually expressed in decimal terms for human convenience. Not all possible numeric values need have a specific meaning. Values without meaning are declared to be unused or reserved for future use. Enumeration is the process of declaring the encoding of human interpretable information in a manner convenient for digital electronic machine storage and interchange. Any subclause that defines a TEDS data field to be enumerated shall contain a table that defines the meaning of the data field for each numbic value possible. The meanings encoded in each data field shall be specific and unique to that data field and only that data field. The value becomes meaningless if not associated with the data field and its defining table.

Event sensor: An event sensor is a sensor that detects a change of state in the physical world. The fact that a change of state has occurred and/or instant in time of the change of state, not the state value, is the “measurement.”

Hot swap: The act of connecting or disconnecting a TIM from a transducer interface medium without first turning off the power that is supplied to the TIM over the medum.

Isochronous transmission: An isochronous transmission is a communications stream transport that is uniform in time. The delivery of the physical stream of information is recurring at regular intervals.

Least significant bit (lsb): The lsb is the bit in the binary notation of a number that is the coefficient of the lowest exponent possible.

Message: A message is information that is to be passed between devices as a single logical entity. A message may occupy one or more packets.

Meta-: A Greek prefix meaning: that which pertains to the whole or overall entity or that which is in common or shared with all member entities comprising the whole.

Meta-TEDS: The collection of those TEDS data fields that pertain to the whole or overall entity or those which are in common or shared with all member entities (TransducerChannels) comprising the whole product.

Multinomial: A multinomial is a linear sum of terms involving powers of more than one variable.

Network Capable Application Processor (NCAP): An NCAP is a device between the Transducer modules and the network. The NCAP performs network communications, TIM communications, and data conversion or other processing functions.

Not-a-number (NaN): As defined in IEEE Std 754‑1985, a bit pattern of a single or double precision real number data type that is a result of an invalid floating point operation.

Octet: A group of eight bits. (In the US an octet is usually referred to as a byte.)

Packet: A packet is information that is to be passed by the physical layer between devices in a single transmission.

Read frame: A read frame is the process of transferring of one block of data from a TIM to the controller.

Sample latched: The term sample latched is used in a sensor to signal that the sample has been acquired. This may be when a sample and hold circuit switches to the hold mode or other similar operation. For an actuator, it signals that the sample has been moved to the output logic.

Sensor: A sensor is a transducer that converts a physical, biological, or chemical parameter into an electrical signal.

Setup time: The time between the initial request for a function to be performed and when the task is actually initiated.

Signal conditioning: Signal conditioning is the transducer signal processing that involves operations such as amplification, compensation, filtering, and normalization.

Smart actuator: A smart actuator is an actuator version of a smart transducer.

Smart sensor: A smart sensor is a sensor version of a smart transducer.

Smart transducer: A smart transducer is a transducer that provides functions beyond those necessary for generating a correct representation of a sensed or controlled quantity. This functionality typically simplifies the integration of the transducer into applications in a networked environment.

Synchronization signal: For the purposes of this standard, a synchronization signal shall be defined as a signal transmitted by the NCAP to provide clock or time synchronization signals to a TIM or group of TIMs. Low cost and performance TIMs may not implement a receiver for the synchronization signal.

Transducer: A transducer is a device that converts energy from one domain into another. The device may either be a sensor or an actuator.

Transducer Interface Module (TIM): A module that contains the TEDS, logic to implement the Transducer interface, the transducer(s) or connection to the transducer(s) and any signal conversion or signal conditioning.

TransducerChannel: A TransducerChannel includes a transducer and all of the signal conditioning and conversion components associated with that transducer.

TransducerChannel address: The concatenation of the TIM alias and the TransducerChannel number that form the logical address of a specific TransducerChannel. The TIM alias is the most significant portion of the TransducerChannel address.

TransducerChannel number: An eight-bit number assigned to an individual TransducerChannel within a TIM by the manufacturer.

TransducerChannel proxy: A device that is created to allow a collection of TransducerChannels to be treated as a single entity. A TransducerChannel proxy is similar to a normal TransducerChannel except that it does not require a TransducerChannel TEDS, it cannot have a Calibration TEDS, Transfer Function TEDS or Frequency Response TEDS. It may support other TEDS. A TransducerChannel proxy may respond to commands.

Transducer Electronic Data Sheet (TEDS): An electronic data sheet describing a TransducerChannel. The structures of multiple TEDS are described in this standard.

Transfer: The act or process of moving information from one digital device to another.

Trigger: A signal or message that is used to start an action.

Trigger cycle: The complete series of activities comprising the assertion of the trigger by the controller followed by the acknowledgment by the TIM.

VectorGroup: VectorGroups are manufacturer specifications that define the inherent relationships between the TransducerChannels of a multi-channel TIM. This VectorGrouping information is not normally used by the TIM itself. This information is normally used by controller applications to properly compose human readable displays or in formulating other computations. For example, VectorGroupings may be used to indicate which TransducerChannels represent the three vector axes of a three-axis vector measurement.

Virtual TEDS: A TEDS that is stored permanently in a location other than the TIM.

Write frame: The process that implements the transfer of data from a controller to a TIM.