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attribute ID and internal gated counting

Dear sir, I have two questions
1) Is it possible to configure all 8 channels of 6602 board as counters and use them with an internal common gate? (I mean: in LabVIEW I want to set a counting time and, just with a single common "start VI", trigger a parallel counting on all channels for a time window that is exactly (within the limits of the osc on the board) the selected counting time.)
It seems that I have always to connect the "Gate" of the counters if I want to do a gated-event counting, so that I do not understand what "internal gate" means. (If, as probable, I am wrong, VI examples would be really welcome!)
2) Where can I find documentation about the "attribute value type" and "attribute value number" I can associate to
every "attribute ID"
(for example in the Counter Set Attribute VI)?
The help seems very poor about these points...


Many thanks in advance!
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Hi!

1) It is possible to perform a buffered event counting on all 660x counters, here you can find an example that performs this operation.

Simultaneous Buffered-Event Counting on All Eight Counters of the 6602 or 6608 Devices
http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=B45EACE3DC9F56A4E034080020E74861&p_node=DZ52325&p_source=External


In Buffered-Event Counting you got to use a digital signal to drive all counters. (see TIO boards manual for Buffered Events Counting details http://digital.ni.com/manuals.nsf/webAdvsearch/DD0DBB6404BC139886256721007CF16D?OpenDocument&vid=niwc&node=132100_US )
If you don't receive this digital signal from the field you can use one of your board time bases (100kHz, 20MHz ...) or generate it with on
e of your board's counter (you'll be able to measure only 7 pulse trains).
I definitely won't suggest you to use a simple event counting and software timing for this kind of measurements, you would loose all the advantages of board's precise timing.

2) You can find all these information in the detailed help of the function (follow the click here for more help link), I can give you an example just to clarify: to use PFI line 19 as your counter gate
attribute ID --> gate selection
In the help you can find valid types:

"Valid values for this attribute are low, source, other counter source, other counter output, in start trigger, in stop trigger, PFI n, and RTSI n. These attribute values are specified using attribute value type control and n is specified with attribute value number control."

In this case:
attribute value type --> PFI n

To specify which PFI lines you'll wire a num. constant "19" at the attribute value number terminal.

H
ope this helps. Ciao.

NicolaC
National Instruments
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