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pwm connected with ramp

Hello everyone!

 

This is an urgent problem to anyone who has some spare time. I amdoing a project at my universaty.And we are using LAbView. I am all new to LabView and what i knownow is what i have learned from tutorial and books. There is one thing i am having trouble with. And that is that i need to make a simple PWM on labview where the results from the PWM willmulitply with a ramp function that i have made. 

 

The problem is that i havent been able to make a simple PWM.I have a USB 6008 model of a DAQ. Can anyone me show or give me a guide to how to solve this? The DC i want it to be is 10% but if u can regulate it as the labview runs it woul be great=). I tried to make something with the Pulse generator that you can find in Daq.But with no louck because when i am cant find anything on the counter I/O that i can add.I have never used it before either. Where you browse to find the I/0

 

I looked around and found this program here which i am adding with this post. It took me sometime before i understood some of the function. but i tried to run it but i cant get the counter to work.

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The counter on the 6008 is an input, not an output, thus counter based PWM output is not possible on the device.

 

-AK2DM

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"It’s the questions that drive us.”
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Is there noe other way to make a PWM without a counter?
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You can make a pwm without a counter, but on the USB-6008 where digital outputs are software timed, the accuracy and timing stability will be very poor.  You could use the Wait or Wait Until Next ms Multiple functions for timing, but expect a lot of jitter in the millisecond to tens of milliseconds range.  If you are doing a heater control where timing in the range of seconds might be acceptable, you could probably do reasonably well with the USB-6008.

 

You do not need the local variable in your VI.  Just wire directly to the Duty Cycle terminal.  Wires are always better than locals.

 

Lynn 

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