02-06-2009 01:28 PM
Hello,
I want to control the on / off of 3 leds.
led 1 led 2 led 3
on off off
off on off
off off on
Then repeat this sequence from a slow start and ramp up to say 3hz over say 20 seconds and then stay at that level untill stopped
Can anyone advise how this might be done ? I would then like to use this to try and control a 3 ph stepper motor.
I am using Version 8.0 if any body can give me some example code to work on.
Labtech5555
02-06-2009 02:12 PM - edited 02-06-2009 02:19 PM
Try something like this, perhaps? Just plug in your desired numbers.
02-08-2009 06:47 AM
Hi Altenbach,
Thanks thats exactly what i am trying to do..Perfect.
Just to take things a little further i would like to plot the three led digital signals 0 or 1 ( True or False) seperately on a graph.
I have tried using digital waveform but as usual i always have major ploblems with data types and converting
or matching up data types for each Vi.
For this example the output from the array is a 1D Array of boolean (true or false).The Vi DWDT Boolean array to digital uses a 2D array.
Checked out the examples but still don't see how to make it work for this example.Tried converting boolean to 1 or 0 and using other graphing
Vi's but still there is a data mis-match.
Any suggestions would be appreciated.
Labtech5555
02-08-2009 11:25 AM
Since the points are not equally spaced in X, you would typically need an xy graph.
Another option would be to run a chart in a parallel loop at regular intervals and read the data via a local variable. See attach example.
03-01-2009 03:57 PM
Hi Altenbach,
The program below works exactly as planned but i want to modify to get another 3 combinations.Can you help for this combination of flashing Leds ?
I can't quite get it working..
I want to control the on / off of 3 leds for the 6 states below:
led 1 led 2 led 3
on off off
on on off
off on off
off on on
off off on
on off on
Then repeat
Thanks,
Labtech5555
03-01-2009 07:34 PM
You can create an array constant containing all of your combinations in order and iterate through them.
03-03-2009 01:22 PM
Hi Ravens Fan,
Thanks for the solution it works as requested.
The problem i have is i have based the original code on a larger program i have written to control real Leds through a DIO card.
The original code was a 1D Array and i could feed this more or less directly to the card without any problems.The code you have
given me uses a 2D Array and i can't feed this directly to the card in the same way without changing alot of the other code i have.
I get an error with data types.
Is there another solution you can think of that uses a 1D Array or is there a way to convert the 2D data ?
Labtech5555
03-03-2009 01:51 PM
It's always a risk that when you start adding new requirements that you didn't originally plan for, you'll be forced to modify more code than you intended.
Notice that I am only sending a 1-D array of the booleans to the indicator. I'm using index array to get out a particular state of booleans (1-D array coming from 2-D array) on any give loop iteration. I'm not saying you should be sending a 2D array directly to a card.
I can't comment on how you should handle it because I haven't seen our your program architecture is working now.
03-03-2009 03:27 PM
From the Index Array output i am taking a wire to Boolean Array to Number ........from this output i can send this to my DIO Card
which outputs this as a Byte to the card output bits 0,1,2.
Unfortunately with this new version using the 2D array this set of wires brings up an error due to a data mismatch.
Thanks for your help.
Labtech5555
03-03-2009 03:46 PM - edited 03-03-2009 03:49 PM
As I said, there is nothing I can comment on unless I see your code.
Preferably the VI itself and not just a screen shot so I can play with it.