system.opc.readValues

This function is used in Python Scripting.

Description

This function is equivalent to the system.opc.readValue function, except that it can operate in bulk. You can specify a list of multiple addresses to read from, and you will receive a list of the same length, where each entry is the qualified value object for the corresponding address.

Client Permission Restrictions

This scripting function has no Client Permission restrictions.

Syntax

system.opc.readValues(opcServer, itemPaths)

Parameters

Type	Parameter	Description
String	opcServer	The name of the OPC server connection in which the items reside.
List[String]	itemPaths	A list of strings, each representing an item path, or address to read from.

Returns

List[QualifiedValue] - A sequence of QualifedValue objects, one for each address specified, in order. Each object contains a value, quality, and timestamp returned from the OPC server for the corresponding address.

Scope

Gateway, Vision Client, Perspective Session

Code Examples

Code Snippet

# This example will read values from a Tag provider called "testSimTags".
# Declare list values for itemPaths parameter
itemPaths = ['[testSimTags]_Meta:Random/RandomInteger1', '[testSimTags]_Meta:Random/RandomInteger1']
 
# Call the system function
system.opc.readValues('Ignition OPC UA Server', itemPaths)