Digital Input Tag Type Properties: I/O Tab
The I/O Tab holds the properties used to identify and establish a connection to the communication driver tag being used to exchange data with your physical I/O device (e.g. PLC or RTU). This is accomplished by identifying the communication driver tag that communicates with the physical I/O device, the address at the physical I/O device from which this tag is to read its data, and the rate at which the I/O device should be scanned for data.
Note: Digital input tags can have single or double bit addresses. Information on single and double bit digital inputs can be found in Single Bit and Double Bit Digital Inputs.
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Select the communication driver tag from which data will be read.
The tag button to the right of the field opens the tag browser, from which you can either select an existing communication driver tag or add a new one. The X button will clear the field. Right-clicking on a tag in the field will open a dialog from which you can the driver`s properties.
The Bit 0 Address property is the address of the low order bit for this tag in the I/O device. If this is a single bit digital tag, this is the field that specifies the address of that bit.
The Bit 1 Address property is the address of the high order bit for the digital input in the I/O device. If this is a single bit digital input, this field should be left blank.
Provide the frequency, measured in seconds, that the I/O device should be scanned for new data.
This optional field allows you to provide a constant value that will be used instead of input read by the communication driver. It is commonly used when testing a new Analog Input tag when application is not attached to a live data source. Tags that are using manual data are marked on screen by a flashing exclamation mark.
The Invert Input checkbox enables you to specify whether or not the value of this tag should be reversed. If selected, the value for this tag will be inverted (i.e. 0 and 1 are swapped).
The typical use for input inversion is in projects where 1 indicates false or off, and 0 indicates true or on. By default, the Invert Input checkbox is not selected.