Data Logs and Buffers

Log data to disk or memory, read data logs

Functions

refreshRead all active items in group
startStart a logging task
stopStop a logging task
waitSuspend MATLAB execution until object stops logging
flushdataRemove all logged data records associated with dagroup object
getdataRetrieve logged records from OPC Toolbox engine to MATLAB workspace
peekdataPreview most recently acquired data
opcreadRead logged records from disk to MATLAB workspace
opcstruct2arrayConvert OPC data from structure to array format
opcstruct2timeseriesConvert OPC data from structure to time series format

Properties

ActiveGroup or item activation state
DeadbandPercentPercentage change in item value that causes subscription callback
LogFileNameName of disk file to which logged data is written
LoggingStatus of data logging
LoggingModeSpecify destination for logged data
LogToDiskModeMethod of disk file handling for logged data
RecordsAcquiredNumber of records acquired
RecordsAvailableNumber of records available in OPC Toolbox engine
RecordsToAcquireNumber of records to acquire for logging session
SubscriptionEnable server update when data changes
UpdateRateRate, in seconds, at which subscription callbacks occur

Topics

Log OPC Server Data

Describes how to log data from an OPC server for later analysis and/or visualization.

Data Change Events and Subscription

Describes how OPC servers generate data change events, and how you can control data change event notification.

Featured Examples