According to the IEC standard, %IW represents an input word register (for example, a language object of type analog IN).
According to the IEC standard, %QW represents an output word register (for example, a language object of type analog OUT).
The model prefix for Altivar drives (for example, ATV312 refers to the Altivar 312 variable speed drive).
A type that is encoded in an 8-bit format, ranging from 00 hex to FF hex.
(continuous function chart) A graphical programming language (an extension of the IEC 61131-3 standard) based on the function block diagram language that works like a flowchart. However, no networks are used and free positioning of graphic elements is possible, which allows feedback loops. For each block, the inputs are on the left and the outputs on the right. You can link the block outputs to the inputs of other blocks to create complex expressions.
(common industrial protocol) When a CIP is implemented in a network application layer, it can communicate seamlessly with other CIP-based networks without regard to the protocol. For example, the implementation of CIP in the application layer of an Ethernet TCP/IP network creates an EtherNet/IP environment. Similarly, CIP in the application layer of a CAN network creates a DeviceNet environment. In that case, devices on the EtherNet/IP network can communicate with devices on the DeviceNet network through CIP bridges or routers.
A network that contains devices connected to a specific communication port of a logic controller. This controller is seen as a master from the devices point of view.
(dynamic host configuration protocol) An advanced extension of BOOTP. DHCP is more advanced, but both DHCP and BOOTP are common. (DHCP can handle BOOTP client requests.)
(device type manager) Classified into 2 categories:
oDevice DTMs connect to the field device configuration components.
oCommDTMs connect to the software communication components.
The DTM provides a unified structure for accessing device parameters and configuring, operating, and diagnosing the devices. DTMs can range from a simple graphical user interface for setting device parameters to a highly sophisticated application capable of performing complex real-time calculations for diagnosis and maintenance purposes.
(electronic data sheet) A file for fieldbus device description that contains, for example, the properties of a device such as parameters and settings.
(function block) A convenient programming mechanism that consolidates a group of programming instructions to perform a specific and normalized action, such as speed control, interval control, or counting. A function block may comprise configuration data, a set of internal or external operating parameters and usually 1 or more data inputs and outputs.
(fast device replacement) A service supported by the device, that facilitate the replacement of an inoperable equipment.
One of the 5 languages for logic or control supported by the standard IEC 61131-3 for control systems. Function block diagram is a graphically oriented programming language. It works with a list of networks where each network contains a graphical structure of boxes and connection lines representing either a logical or arithmetic expression, the call of a function block, a jump, or a return instruction.
Variable that indicates the communication state of the channels.
Represents the maximal time (in ms) between a request of the Modbus IO scanner and a response of the slave.
(instruction list) A program written in the language that is composed of a series of text-based instructions executed sequentially by the controller. Each instruction includes a line number, an instruction code, and an operand (refer to IEC 61131-3).
Assemblies are blocks of data exchanged between network devices and the logic controller. An Input Assembly generally contains status information from a slave or Target device, read by the master or Originator.
(integer) A whole number encoded in 16 bits.
(ladder diagram) A graphical representation of the instructions of a controller program with symbols for contacts, coils, and blocks in a series of rungs executed sequentially by a controller (refer to IEC 61131-3).
(media access control address) A unique 48-bit number associated with a specific piece of hardware. The MAC address is programmed into each network card or device when it is manufactured.
(open DeviceNet vendors association) The family of network technologies that are built on CIP (EtherNet/IP, DeviceNet, and CompoNet).
In EtherNet/IP, the device that initiates a CIP connection for implicit or explicit messaging communications or that initiates a message request for un-connected explicit messaging.
See also target
Assemblies are blocks of data exchanged between network devices and the logic controller. An Output Assembly generally contains command sent by the master or Originator, to the slave or Target devices.
(program organization unit) A variable declaration in source code and a corresponding instruction set. POUs facilitate the modular re-use of software programs, functions, and function blocks. Once declared, POUs are available to one another.
Polling interval of the Modbus request that is sent.
A standard type of 8-pin connector for network cables defined for Ethernet.
(requested packet interval) The time period between cyclic data exchanges requested by the scanner. EtherNet/IP devices publish data at the rate specified by the RPI assigned to them by the scanner, and they receive message requests from the scanner with a period equal to RPI.
(structured text) A language that includes complex statements and nested instructions (such as iteration loops, conditional executions, or functions). ST is compliant with IEC 61131-3.
In EtherNet/IP, a device is considered to be the target when it is the recipient of a connection request for implicit or explicit messaging communications.
See also Originator
(underwriters laboratories) A US organization for product testing and safety certification.
A memory unit that is addressed and modified by a program.
