Driver modification problem

[RRAMIR]

Hello,

I am trying to write a simplified code for a power meter using the drivers that the power meter came with.  I am having trouble decifering what is what and am overwelmed at the fact that there are 41 sub VI's associated with this driver.  I am a begining LabVIEW user so I am looking for guidance as to how I can complete this task efficiently without wasting more time. 

Thanks

[smercurio_fc]

You should help us to try to help you by, for example, providing information as to:

• what kind of power meter you are using
• where did you get the drivers (is there a link where we can actually download them so we can see them)
  
• what you're trying to change

[RRAMIR]

Hello All,

Sorry for the lack of details, I am new to this and appreciate your patients. 

• I have a Thorlabs;
  

  PM120
  Digital Optical Power Meter w/ S120B Sensor, 50nW-50mW, 400-1100nm (http://www.thorlabs.com/thorProduct.cfm?partNumber=PM120)
  

• The drivers can be found at (http://www.thorlabs.com/software_pages/PM100.cfm)
• I really just want to read the power in time intervals of one second or so. 
  
• The one second interval is to allow for translation of stage by hand or actuator.
• Most likely an actuator will be purchased for the stage translation in which case the code will have to be modified later. 
  

Thanks for your reply
Rafael

[smercurio_fc]

Well, I can't really tell you what each of those VIs do since they basically implement the meter's functionality. If you open each of those VIs and have the context help window open (Help -> Show Context Help) and place the cursor over the VI Icon in the upper right of the window you will see a description of the VI.

A basic sequence to read the power would likely be:



If you want to read the meter once a second you can do something as simple as this:




Message Edited by smercurio_fc on 05-21-2008 03:38 PM

[RRAMIR]

Hello Smercurio_fc, 

Thanks for all your help,

I came up with something that I kind of understand and might work.  The only problem I am having is that the intervals I timed are not exactly one second, How can I fix this?

I am getting power readings but the intervals are not exactly one second apart. 

Thanks
Rafael

[RRAMIR]

Hello Smercurio,

I tried running the first sample VI and I couldn't for the life of me figure out why it wasn't working. 

Also how was it that you determined those VI's you selected from the driver list where the ones we needed?

I have attached my set up and the error message

Thanks for your time

[smercurio_fc]

---

I came up with something that I kind of understand and might work.  The only problem I am having is that the intervals I timed are not exactly one second, How can I fix this?

---

The Instrument I/O Assistant and Write to Measurement File add overhead, so that's probably why you're not seeing "exact" 1 second intervals.

---

I tried running the first sample VI and I couldn't for the life of me figure out why it wasn't working. 

---

You probably need to set the baud rate. The "PM100 Initialize" VI has a "baud rate" input, which defaults to 115200. Is this the baud rate you were using? That error code is not a LabVIEW error code. Could be a LabWindows error code. The only info I found said it meant "Data corrupt or stale". Doesn't make much sense for it to come from the Initialize VI.

---

Also how was it that you determined those VI's you selected from the driver list where the ones we needed?

---

The Initialize and Close are fairly standar functions. Then, I just looked for a VI that was named something along the line of what I was trying to do, which was to read. As I noted, opening the VIs and having the context help window open will help considerably, as it provides a description of the VIs.

[RRAMIR]

Hello Smercurio,

Ya, I did modify the baud rate but was still getting that error. 

Thanks

[smercurio_fc]

I honestly don't know what else to suggest, as the Initialize VI simply calls that LabWindows DLL, and that error code doesn't mean much to me. I could find no documentation on it other than what I already mentioned.

[chris_amadasun]

Hello,
Can you verify that you are using the right VISA runtime engine 3.0?
Have you followed the entirety of that readme for that driver and place any dll in the right directories?