How will you convert a high frequency digital pulse into low frequency pulse

[NI 6602 Pulse divider]

Hi,

At present, I am using pulse delay generator NI program for triggering some of my systems. The signal is picked up from High speed rotating flywheel. Until now, I am using an Pulse divider( elctronic circuit) to convert the high frequency signal from the flywheel to low frequecy pulse. Now I have to replace this one with an NI program. Could anyone please help me in fixing this issue? I have attached the Pulse delay generator NI program along with this mail. Is it possible to change anything in this to accept high frequency pulse and convert into an low frequency pulse within the Pulse delay generator NI program.

The details of my NI systems are

1.        NI PXI 1031 ( With NI PXI – 8184 Embedded controller, NI PXI – 6602 Timing I/O) { P/O: 190871D-01 Rev 1.1 & S/O: 118AB77)
2.       SCB – 68 (P/N: 182469D-01 & S/N: 11AB6DE)

Thanks.

Regards,

Kannan R

[NathanS]

Hi Kannan,

Sounds like you probably need to divide down the frequency. Have a look at this thread and the VI it contains:

http://forums.ni.com/t5/Counter-Timer/frequency-divider-narrow-pulse-output/td-p/654785

Regards,

[NI 6602 Pulse divider]

Hi Nathan,

Thank you very much for your reply. Could you please help me to modify the pulse delay generator NI program in such a way that the high frequency can be converted into a low frequency signal with a frequency of my interest?

Thanks.

Regards,

Kannan

[NathanS]

---

Could you please help me to modify the pulse delay generator NI program in such a way that the high frequency can be converted into a low frequency signal with a frequency of my interest?

---

Hi Kannan,

I am wondering, what are the frequencies of the high frequency signal and the low frequency signal you are interested in?

Regards,

[NI 6602 Pulse divider]

Hi Nathan,

Thank you very much. The input signal frequency will vary from 5 Hz to 100 Hz. The frequency of the output signal has to be less than 1 Hz. The output signal frequency has to be a variable. This output signal has to be used as trigger signal for triggering my devices with different delays. At present, I am using Pulse delay generator NI code and I am giving low frequncy signal as a input. The low frequency signal was obtained using Pulse divider circuit from a high frequency signal source. Now I have to replace that circuit and the process has to be done within the Pulse Delay generator NI program itself.

Thanks.

Regards,

Kannan

[NathanS]

Hi Kannan,

See the modified code that is attached. I simply combined the example I mentioned to you before with your code. I have no way of testing it, so you may need to modify it to fit your specific application. You will need to set values to divide by on the block diagram in the array of constants I added for each of your signals in order for this code to work at all.

Regards,

Nathan Scharfe

Applications Engineer

National Instruments

http://www.ni.com/support

The attached Code is provided As Is. It has not been tested or validated as a product, for use in a deployed application or system, or for use in hazardous environments. You assume all risks for use of the Code and use of the Code is subject to the Sample Code License Terms which can be found at: http://ni.com/samplecodelicense

[NI 6602 Pulse divider]

Hi Nathan,

Thank you very much. I have Labview 10 only. Could you please save this code in Labview 10 and send that thing to me.?

Thanks.

Regards,

Kannan

[NathanS]

Hi Kannan, 

Please try this one.

Regards,

[NI 6602 Pulse divider]

Hi Nathan,

Thanks. I am getting error message. I have attached the screen shot along with some explanation as a doc file here.  Please see the attachement.

Could you please change something here? I am going to give high frequency signal (5 to 100 Hz) as a Trigger source, i.e., /PXI1slot2/PFIO. Here this has to be converted or divided into low frequency signal (1Hz). This signal has to be used in the program for generating output signal with delay from Channel 0 parameters to Channel 7 parameters. Please help me to address this issue.

Thanks.

Regards,

Kannan.

[NathanS]

Hi Kannan,

You will need to put the division factors for each of your 8 channels into the constants on the block diagram. I simply wired 0 constants to the array builder, but you can't run the program that way; that's why you got an error. Calculate the number N which you need to put in each constant to divide it's channel's frequency down to the frequency you desire. 

By the way, you may want to take a different approach to solving this problem. Instead of trying to write a VI which does everything you want all at once, you might want to try breaking the problem down into smaller pieces and solving each piece individually. For example, just try to divide down a single high frequency channel first. Then, once you know how to do that, you might be able to write a more advanced program to do it for all 8 channels. 

Regards,