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| ANSI | American National Standards Institute. |
| Application Programming Interface (API) | A collection of functions used by a user application to access hardware. Within NI-DNET, you use API functions to make calls into the NI-DNET driver. |
| ASCII | American Standard Code for Information Interchange. |
| attribute | The externally visible qualities of an object; for example, an instance square of class geometric shapes could have the attributes length of sides and color, with the values 4 in. and blue. Also known as property. |
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| b | Bits. |
| bit strobed I/O | Master/slave I/O connection in which the master broadcasts a single strobe command to all strobed slaves, then receives a strobe response from each strobed salve. |
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| CAN | Controller Area Network. |
| change-of-state I/O | Master/slave I/O connection which is similar to cyclic I/O, but data can be sent when a change in the data is detected. |
| class | A classification of things with similar qualities. |
| connection | An association between two or more devices on a network that describes when and how data is transferred. |
| controller | A device that receives data from sensors and sends data to actuators to hold one or more external, real-world variables at a certain level or condition. A thermostat is a simple example of a controller. |
| COS I/O | See change-of-state I/O. |
| cyclic I/O | Master/slave I/O connection in which the slave (or master) sends data at a fixed interval. |
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| device | A physical assembly, linked to a communication line (cable), capable of communicating across the network according to a protocol specification. |
| device network | Multi-drop digital communication network for sensors, actuators, and controllers. |
| DeviceNet interface | A physical DeviceNet port on an AT-CAN, PCI-CAN, PCMCIA-CAN, or PXI-8461 interface. |
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| expected packet rate | The rate (in milliseconds) at which a DeviceNet connection is expected to transfer its data. |
| explicit messaging connection | General-purpose connection used for executing services on a particular object in a DeviceNet device. |
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| hex | Hexadecimal. |
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| I/O connection | Connection used for exchange of physical input/output (sensor/activator) data, as well as other control-oriented data. |
| individual polling | A polled I/O communication scheme in which each polled slave communicates at its own individual rate. |
| instance | A specific instance of a given class. For example, a blue square of 4 inches per side would be one instance of the class Geometric Shapes. |
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| KB | Kilobytes of memory. |
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| LabVIEW | Laboratory Virtual Instrument Engineering Workbench. |
| local | Within NI-DNET, anything that exists on the same host (personal computer) as the NI-DNET driver. |
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| MAC ID | Media access control layer identifier. In DeviceNet, a device's MAC ID represents its address on the DeviceNet network. |
| master/slave | DeviceNet communication scheme in which a master device allocates connections to one or more slave devices, and those slave devices can only communicate with the master and not one another. |
| member | An individual data value within an array of DeviceNet data bytes. |
| method | An action performed on an instance to affect its behavior; the externally visible code of an object. Within NI-DNET, you use NI-DNET functions to execute methods for objects. Also known as service, operation, and action. |
| multi-drop | A physical connection in which multiple devices communicate with one another along a single cable. |
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| NI-DNET driver | Device driver and/or firmware that implement all the specifics of a National Instruments DeviceNet interface. |
| notification | Within NI-DNET, an operating system mechanism that the NI-DNET driver uses to communicate events to your application. You can think of a notification of as an API function, but in the opposite direction. |
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| object | See instance. |
| ODVA | Open DeviceNet Vendor's Association. |
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| olled I/O | Master/slave I/O connection in which the master sends a poll command to a slave, then receives a poll response from that slave. |
| protocol | A formal set of conventions or rules for the exchange of information among devices of a given network. |
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| remote | Within NI-DNET, anything that exists in another device of the device network (not on the same host as the NI-DNET driver). |
| resource | Hardware settings used by National Instruments DeviceNet hardware, including an interrupt request level (IRQ) and an 8 KB physical memory range (such as D0000 to D1FFF hex). |
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| s | Seconds. |
| scanned polling | A polled I/O communication scheme in which all poll commands are sent out at the same rate, in quick succession. |
| sensor | A device that measures electrical, mechanical, or other signals from an external, real-world variable; in the context of device networks, sensors are devices that send their primary data value onto the network; examples include temperature sensors and presence sensors. Also known as transmitter. |
| strobed I/O | See bit strobed I/O. |
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| VI | Virtual Instrument. |