12-17-2006 06:00 PM
Hello,
How can a staircase waveform be created in Labview. I have attached the waveform needed.
Ams
12-17-2006 10:53 PM
Hi Ams,
The attached vi will generate one cycle of a staircase waveform
Hope this helps,
Regards,
Dev
12-18-2006 12:35 AM - edited 12-18-2006 12:35 AM
Message Edited by altenbach on 12-17-2006 10:36 PM
12-19-2006 01:19 AM
hello,
both the earlier queries are regarding the staircase ; i somwhat understood the VI you sent me but the reshape part is not clear ; i am not sure why it is there, i think you are using it to plot but should it not be just a 2 D array. Is it true that the graph is only plotted when the entire array is filled up i.e the loops have been completely executed.
Ams
12-19-2006 01:47 AM - edited 12-19-2006 01:47 AM
Message Edited by altenbach on 12-18-2006 11:47 PM
12-21-2006 02:38 PM
Hello altenbach,
The staircase waveform works great . Thanks a lot for that . However I have run into another difficulty. I am trying to use it as a trigger and I have a way of using the staircase as a trigger by sending it's output to the trigger input and then using a counter however for certain reasons I need to get a square pulse trigger from the same staircase program maybe by putting a second DAQ output (I already put one to get the waveform out).
So essentially I am trying to get a signal out whenever the 1st step is executed in a cycle by using an If condition to check the iteration in the for loop . The problem is that I get an error message since there is an array comparision going on and I need a boolean o/p for trigger.
12-21-2006 02:50 PM
Well, that won't work.
First of all, LabVIEW starts counting with zero, so use the premade "=0?" node. 😉 Easiest would be to generate a signal with the same number of points, it is just mostly zero.
You probably want to do the comparison inside the loop, then feed it to a switch where you select between the ON and OFF trigger voltage. Autoindex out the array and treat it like the existing one.
04-06-2007 01:08 PM
Altenbach,
I need a modification on the staircase waveform you sent me (I have attached it). The next staircase starts as soon as the previous one finishes. However I need a waiting period where the next waveform waits for a used defined time before starting the next staircase ; alternatively the 1st step of the next staircase is a much longer one (user defined)
A couple of ideas
1) Add a wait time function (within the outer loop) which is user defined so that the next staicase waits until that time elapses (Done if step =1 for a particular cycle) .
2) Add another new time step control and a check inside the loop (if step =1 for a particular cycle then use a different new step time control else use the default step time)
So we still have the staircase but with an elongated 1st step .
Please help me implement this in labview.
Ams
04-06-2007 01:32 PM
04-06-2007 04:21 PM
Lynn,
The code you sent me does not give me a staircase waveform. I have attached the O/P I saw on my end (below that is the staircase I currently get). What I want is a staircase with a time gap between the end of one cycle and the start of a new one. What should I feed into the intercycle interval if I want a 0.2 sec separation.
Aman