LeCroy not listening

[anbere]

Not sure why, but my LeCroy waverunner 6030 is not listening to the commands I send. For instance, I wire DC coupling to channel config (in labview 8.0), and it sometimes gives me AC coupling anyway....and the range command i'm trying to send just get lost in space and i get 1.26V/div regardless of what i'm sending. I use LCWAVE.

I checked the examples again to make sure everything was set up correctly, and it is. In fact, when i run the example, i also get 1.26 V/div even though it should be 10.

Also, as a side question, is it possible to configure a channel with LCWAVE when there's a current probe on it? I keep getting some errors that are fixed if i remove the current probe.

So if you have any clue i'd be thankful!

[alanjb]

Hi anbere,

Another customer reported issues with setting coupling when using current probes, and I've included a fix in the next version.  I've attached a "development" version to this posting.  Please exit LabVIEW, backup your existing instr.lib/lcwave folder, and then install this version of the driver.  Let me know if this solves the problem.

Thanks,
Alan

[anbere]

I still have issues.....For some reason the scales still won't set at all...Current probe on or not.  The  coupling now seem to work (on channel 1, voltage probe), but it seems random because i can't configure the channel 2 (when i put the probe on) so i can't specify the actual coupling. When i add a box configure channel for the channel 2 and try to run the program, i get  Error -1074000000 occurred at an unidentified location  so the drivers didnt fix it.

Possible reason(s):
 LCWAVE Error Query;
instrument reports:
Unrecognized keyword.

Also it is a bit weird because i set the trigger level on ext at 1V and i get 410mV instead of 1..

Timebase works, offset works, data acquisition works.

Message Edited by anbere on 06-04-2008 11:02 AM

[alanjb]

Hi Anbere,

Regarding the range, note that Configure Channel programs the full scale range, and not the volts/div.  Since there are 8 vertical divisions, sending in 10 will result in 1.25 V/Div.

The external trigger might simply have a maximum of 410mV.  Configure it manual on the scope... What's the maximum you can set?  The driver does not include range checking, so this is something that you'll need to verify.

The Unrecognized keyword most likely means that you are setting up a value for coupling that isn't appropriate for the channel.  For example, if you don't have a current probe attached, selecting "AC" or "DC" for the coupling rather than "A1M", "D1M" or "D50" will return -1074000000.

Best Regards,

Alan

[anbere]

Thanks for those tips. It's working better now, though i still have small problems like the scales set itself to 50mV after a while (i programmed 500)....Also, i'm acquiring data and sending it in labview in a iterative process, and sometimes everything work perfectly and i get to see (let's say) all 10 iterations....and sometimes it just don't and i see like the first one only or none (while stille hearing the small sounds the source and scope make at each iterations).....Not sure why this happen....Trying to fix it, but i hate those "sometimes it works sometimes not " kind of problems...

Edit : oh and about the ext trig it can go up to 4.10V.....when i use the program it's written 410mV in the bottom right corner, but if i click on it it says 1V and when i close it back it stays at 1V....till i run my program again then its back to 410mV

Message Edited by anbere on 06-04-2008 02:06 PM

[alanjb]

Hi Anbere,

One thing that can happen that causes problems with iteratively changing the volts/div is that the scope might need to perform a calibration cycle.  If you haven't accounted for this in your code, then you might go through multiple iterations during the cal cycle, and thus end up missing iterations. Do you think this is what's happening? I'll workup a suggested command sequence for you.

Can you provide more detail about how the scope is "setting itself to 50mV"  ? Note that the scope has a "Remote Control Assistant" that logs the commands that you are sending to it.  This is very useful for debugging.  Go to Utilities - Utilities Setup..., and then to the "Remote" tab.  On this tab is a button to show the remote control assistant, and a selection for the logging mode. You'll want to use "Full Dialog" rather than "Errors Only".

Regarding the external trigger settings... Can you email me a screenshot or two showing what you are clicking on where it shows 1V?

Best Regards,
Alan

[anbere]

do not read this, i screwed my post


Message Edited by anbere on 06-06-2008 11:13 AM

[anbere]

Thank you alan. I got some things that came and are of absolute priority, so I got to put that automation work aside for now, i'll get back to you with screenshots next week if you want.

But it's pretty simple: about the trigger, theres a box at the bottom right that show the trigger coupling, edge, trigger level...etc. it is set on ext/10

0-I send trigger level 1V with labview

1-right now it is shown 410mV.

2-I click on the box to enter the menu

3-I see that the box to set the level is not at 410mV, but at 1V

4-I exit and i now see trigger level 1V in the bottom right box

I think that's because I send the command external with labview for the trigger source (i cannot send ext10) and it gives me ext10.....ext max is at 410mV, while ext/10 4.17 V, so that look like the same channel. the real maximum must be 410mV then, and the ex/10 must be when you put on a X10 probe, wich is not my case.

so it's not an issue, let's forget that, the only thing i'm not sure is why it is set to ext/10, but it doesn't really matter to me.

About the calibration, i think you may be right, i have not included anything in my program to cope with that. And it does seem like its happening like you said. I will be sending pulses of about 100us at up to 3600A in supraconductor ruban to find their critical current. So I don't wanna miss any critical points because i'll be taking way too much mesurements to notice what i may have missed and it would be bad to notice that later when working on the data. Err that sentence was hard to get ("kind of") right. sry for my english anyway.

Thanks again for all your help you should come live in my living room. i'd need it.

Message Edited by anbere on 06-06-2008 11:10 AM

[alanjb]

Hi Anbere,

It looks like the driver makes a decision to program EXT or EXT/10 based on the requested trigger level. This is a workable approach, but it isn't obvious to the user.  I will ask NI why they chose to do it this way. I think it makes more sense avoid such decisions, and instead let the user explicitely set scope properties as they would do when operating manually...

Best Regards,

Alan

[NathanT]

Hello Alan and Anbere,
          When I look through the project-style driver (just searched for "EX10"), I just see the EX and EX10 being selected by the user as channels, not arbitrarily assigned by the driver based on trigger level.  Could you please show me where the trigger level logic of EX or EX10 is occuring?

Thank you,

NathanT