lcaNewMonitorValue

Calling Sequence

[flags] = lcaNewMonitorValue(pvs, type)

Description

Check if monitored PVs need to be read, i.e, if fresh data are available (e.g., due to initial connection or changes in value and/or severity status). Reading the actual data must be done using lcaGet.

Parameters

pvs

Column vector (in matlab: m x 1 cell- matrix) of m strings.

type

(optional argument) A string specifying the data type to be used for the channel access data transfer. The native type is used by default. See here for more information.

Note that monitors are specific to a particular data type and therefore lcaNewMonitorValue will only report the status for a monitor that had been established (by lcaSetMonitor) with a matching type. Using the “native” type, which is the default, for both calls satisfies this condition.

flags

Column vector of flag values. A value of zero indicates that no new data are available – the monitored PV has not changed since it was last read (the data, that is, not the flag). A value of one indicates that new data are available for reading (lcaGet).

NOTE: As of labCA version 3 the flags no longer report error conditions. Errors are now reported in the standard way, i.e., by aborting the labCA call. Errors can be caught by the standard scilab try-catch-end construct. The lcaLastError routine can be used to obtain status information for individual channels if lcaNewMonitorValue fails on a vector of PVs.

See also lcaNewMonitorWait.

Examples

try and(lcaNewMonitorValue(pvvec))
	vals = lcaGet(pvvec)
catch
    errs = lcaLastError()
	handleErrs(errs)
end