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The ; is Being Ignored When I am Externally Triggering a Scan List. on the SCXI-1127

Hardware: SCXI>>Modules>>SCXI-1127

Problem:
I would like the first trigger I receive to close a connection on the multiplexer.  When I call the niSwitch Initiate.vi the first item in the Scan List is executed so I placed a wait for trigger at the beginning of my Scan List. 

;
ch0->com0;
;
~ch0->com0 && ch1->com0;

When I initiate the Scan List or use an external signal to trigger, the ;'s (semi-colons)  are being ignored. 

Solution:
When you have multiple SCXI-1127's, the ;'s (semi-colons) are used to synchronize the two devices so they act as a wait for trigger command. 

When you have a single module, there are no other modules to synchronize with, so the semi colons are ignored.  This means that when you initiate the Scan List, instead of waiting for a trigger, the ; (semi-colon) is passed and the ch0->com0; command is run instead.  The same thing happens when a trigger comes in.  The next ; (semi-colon) is ignored and the ~ch0->com0 && ch1->com0; command is run instead. 

Related Links: Product Manuals: NI-1127 Specifications
Product Manuals: NI Switches Help
KB 30J9TOZO: What are the scanning options for the SCXI-1127/1128 Switch Module?

Attachments:





Report Date: 10/18/2007
Last Updated: 10/19/2007
Document ID: 4EHITD9S

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