how to convert a char string into an array

[kevinhy]

This part is working fine now, Thanks for all your suggestions! They really helps and opens up my mind. How my program works(it is use to control a step motor) and the motor runs. The only problem now is that after the first iteration(I put everything in a while loop) labview crashes, everything just shuts. All labview windows are closed. Any guess what could have gone wrong?

[tbob]

You will need to post your code so that we can look at it. One thing to look at is that all while loops should have some time delay to allow for CPU to handle other processes. Also, make sure you aren't opening files in a loop without closing them within the loop, or creating VISA sessions in the loop without closing them in the loop. Opening/Creating should be done before the loop, and closing should be done after the loop.

[kevinhy]

Thanks again, this is the vi.

[tbob]

It looks like you are initializing a port in your first frame, then reading from the port and writing to the port in the next two frames. When the loop repeats, you are initializing an already initialized port again. This may be why it crashes. Try moving the first frame out of the loop and run it before the loop. Your loop should just read and write. After the loop, you should call a function to close the port.

[coolitsmaddy@rediffmail.com]

I'm trying call a dll with input type unsigned char, I have to convert integer array to unsignedchar..

Thanks in advance..

[kevinhy]

in the function panel, go to numerical---->conversion---->byte array to string function may just do the job.

Kevin

[coolitsmaddy@rediffmail.com]

thanks Kevin,

 But i made a mistake in posting i wanna pass pointer to char string..I found code creating a array pointer and reading array in LV. 

[kevinhy]

Here is how I  understand your question: you have a dll function that needs to be fed a pointer of char.  Labview does not differentiate a pointer from an array.  so all you have to do is to feed your dll function with an array of the type char, you may want  to try to use created an array function to generate the required char array.  it can be found where you get your initialize array function.

kevin

[coolitsmaddy@rediffmail.com]

@kevin

U understood my problem correctly..Bu t i didn't understood "you may want  to try to use created an array function to generate the required char array.  it can be found where you get your initialize array function".

[paulmw]

I think all you need to do is to change the data type in your example to a U8 (i.e. char) instead of an I32.

Message Edited by paulmw on 09-29-2009 08:22 AM