Gettrighandler (line), Settrighandler (lines, func), Waitfortrig (controller, line, timeout) – National Instruments NI-VXI User Manual

Page 94: Map trigger functions, Map trigger functions -56, Maptrigtotrig -56

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Chapter 3 Software Overview

NI-VXI User Manual

3-56

© National Instruments Corporation

GetTrigHandler (line)

GetTrigHandler

returns the address of the current trigger handler for

the specified VXI trigger line.

SetTrigHandler (lines, func)

SetTrigHandler

replaces the current trigger handler for the specified

VXI trigger lines with an alternate handler.

WaitForTrig (controller, line, timeout)

You can use the

WaitForTrig

function to suspend operation until it

receives a trigger configured by the

EnableTrigSense

function.

After a call to

EnableTrigSense

for a particular VXI trigger line

protocol, the trigger handler for a specific trigger line is called when
the sourced trigger is sensed from the sourcing device. You can use

WaitForTrig

as an alternate method for receiving sensed triggers by

having the caller wait until the trigger occurs instead of installing a
callback handler. The current handler is invoked regardless of whether
a

WaitForTrig

call is pending.

Map Trigger Functions

You can use the NI-VXI map trigger functions as configuration tools
for multiframe and local support for VXI triggers. You can configure
the triggering hardware to route specified source trigger locations to
destination trigger locations by using the

MapTrigToTrig

and

UnMapTrigToTrig

functions.

MapTrigToTrig (controller, srcTrig, destTrig, mode)

MapTrigToTrig

configures triggering hardware to route specified

source trigger locations to destination trigger locations with some
possible signal conditioning. The possible values for source or
destination locations are the TTL trigger lines, ECL trigger lines,
Star X lines, Star Y lines, or miscellaneous external sources.
Miscellaneous external sources include front panel trigger ins, front
panel trigger outs, local clocks, and crosspoint switch locations. The
mode parameter specifies how the line is to be routed to the
destination. You can manipulate the line in various ways, including
inverting it, synchronizing it with the CLK10, or stretching it to a
minimum time. In this way,

MapTrigToTrig

can be used as a simple

map from an external source to a trigger line, or as a complex

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