Setting output pin to high while counter counts edges - 660x

Traditional DAQ allowed you to set the output of a counter while it counted, is there an equivalent for daqmx? The counter output for our current setup spins a motor until the counter reaches the proper number of counted edges from another pulse generator on the board. Perhaps I need to reconsider the setup, but there should be a method to do this action. I was only able to find an indicator of the output state in the Channel property nodes. Any ideas? Thanks.

Hello Roth,
An event is thrown whenever a counter reaches its terminal count, and you should be able to use that to your advantage here. Once that terminal count is reached, you can use DAQmx properties to set the counter to output a pulse or toggle the line. If you use this property in conjunction with the initial count property, you can have the counter cound X number of edges and then toggle the output line:
I hope this helps!
Thanks,
Justin M.
National Instruments
Message Edited by Justin M. on 06-12-2006 01:05 PM
Attachments:
Terminal Count Toggle.JPG ‏11 KB

Similar Messages

Counter Output Pin on PCI-6229

I am using NI-DAQmx 7.3 C API with (among others) a PCI-6229.
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Is that expected?
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Phone (503) 620-3001
Fax (503) 620-6754
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Salvador Santolucito wrote:
Hi John,
I would suggest using the DAQmxTristateOutputTerminal. I have tried what you are doing in LabVIEW and I'm seeing the exact same results. When I set the default pin to tristate, the counter output does not show up on it.
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CDAQ module for high speed pulse counting

I need to know a USB module which can be used for pulse counting. The pulses are generated from an encoder attached with an stepper motor. It generates 15 pulses per step.Pulse amplitude is 0 to 5V. I am using a compact DAQ system (ni 9178).

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Hello, I would like to produce 2 different pulse trains on the CTRo and CTR1 output pins.

(DAQ-CARD E6024 PCMCIA)I have the 2 output pins monitored on my scope, when CTR0 puts out a pulse train, CTR1 goes high. When CTR1 puts out a pulse train CTR0 goes high. Also, the pulses are interleaved with each other. Is there a way to make then start at the same time
Attachments:
Stim_Output_pulses_CTR_0,1.vi ‏94 KB

Hello Zoltan,
I would suggest using the counter gates to synchronize the counters. You will need to externally run a wire from one of the DIO lines you're not using to one of the counters' gates. When the counter gate is high, the pulse train will be generated on each counter. Both counters will need to use the same PFI line as the gate.
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I'm currently using Count Buffered Edges.vi to do Buffered Event count with the following settings,
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thks and best regards
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Hi,
I have tried the same example, and used a 100Hz signal on the gate. I increased the buffer size to 2000 and I did not get any errors. The buffer size does not get smaller when increasing the frequency of the gate signal; simply, the number of counts gets smaller when the gate frequency becomes larger. The buffer size must be able to contain the number of counts you want to read, otherwise, the VI might not function correctly.
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Dear All,
I am using LabVIEW 8.5 on 32-bit Windows XP with an NI 6602 DAQ board. In the past I've used DAQmx but for compatability with older software I need to do a few simple things using Traditional DAQ, which I have never used. Specifically I would like to make a simple VI that sets PFI 5 to high when the user presses a button and then low when they press the button a second time. How do I set PFI 5 for output and then write true to it?
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Solved!
Go to Solution.

Dear All,
Apparently its as simple as using the Write to Digital Line VI. However, the non obvious thing is the port width of the 6602 board is 32 not the default 8. Buried in the LabVIEW help files is a list of physical port widths that one must stumble upon. Like the bat cave. In the attached image of the super simple VI I've made the 16 refers to PFI 16. Good to know.
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Attachments:
write_low.JPG ‏5 KB

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Hi everyone,
I am using a PCI 6122 (S Series, DAQ-STC) and Labview 7.1 on a Windows XP. There are only two counters on this card (Ctr 0 and Ctr 1) and I need to use both of them to count edges. While testing the counters, I am inputing a TTL signal of 10kHz to the Gate of each counter, to be used as an external sample clock, and a 20Hz TTL signal into the Source of each counter, to be used as the input signal. Ctr 0 counts 40 edges per second, i.e. twice as many as it should, while Ctr 1 is reading the correct number of edges, i.e. 20 edges per second.
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Thanks.
Solved!
Go to Solution.

After many tests on my own and after speaking with a NI engineer and repeating some tests over the phone, it seems like there is something wrong with the (one) counter on the board. I have sent it back for repairs (thankfully, it was still under warranty .
Message Edited by DanceWiz on 09-15-2009 09:58 AM

Having count- count(count(1))

I have two queries below- first of which outputs one record, the Second query doesn't.
Can you explain why First query returns always records, at least one record? In explanation, can you say which process is runned after which (something like where is runned firstly, then group by, then...)?
--First:
select count(count(1)) from dual
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--Second:
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Hi,
Aggregate queries with nested aggregate functions (such as "COUNT (COUNT (1))") always return exactly 1 row, even if there are no rows in the table (or, as in your first example, no rows survive the WHERE clause).
The outer layer of nested aggreate functions is evaluated after the GROUP BY and HAVING clauses have been applied.
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You can think of things as happening in this order
(1) WHERE
(2) GROUP BY
(3) (inner) aggregate fucntions
(4) HAVING
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The optimizer may not actually follow the steps above, but you won't notice that.
Edited by: Frank Kulash on Mar 25, 2010 11:51 AM
The following thread may help you:
Re: group function

Le noeud de méthode "Set Output Enable"

Bonjour,
J'ai un NI cRIO 9074 avec un module NI TTL High-Speed Digital input/output 9401et je veux savoir si c'est possible d'utiliser un noeud de méthode "Set Output Enable" et comment le configurer car j'arrive pas a trouver la configuracion pour cette option et j'ai le besoin pour finir mon projet.
Merci
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Thank you

Bonjour ,,
Cette question a déja été posée sur notre forum,
http://forums.ni.com/t5/LabVIEW/How-do-you-configure-a-cRIO-9401-for-output/td-p/365842
Je vous souhaite une bonne journée,
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Measurementbench.vi ‏143 KB

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Best Regards,
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HI,
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Setting output pin to high while counter counts edges - 660x

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