T7 Streaming Different Values than CR | LabJack
 
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T7 Streaming Different Values than CR

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_rednax_
_rednax_'s picture
T7 Streaming Different Values than CR

Hello, 

I've been working on a piece of software to stream from both a T4 and a T7 at the same time through direct Modbus, and up until now it has been working fine. However, today I tried to start it up, and while the T4 worked fine, the T7 is reading -5.28V when pulled to ground (where it should obviously be reading 0). Thinking it was something to do with retrieving the calibration from flash, I switched to nominal calibration provided on your website, but still was getting the weird values. I then tried to factory reset in case I had acidentally written to an obscure register by accident, but again it didn't do anything.

Finally, I tried streaming with LJstreamM to see if it my software or something else altogether. I began by pulling AIN0 to ground, and before I started the stream (when LJstreamM is using command response to communicate) it was reading 0V as it should (see first attached screenshot). This was also the case when viewed through kipling/commmand response through modbus. I then started the stream while still pulling AIN0 to ground, and it again jumped to -5.28V immediately (second screenshot). All the software was working perfectly last Sunday when I was last working on it, and I made no register changes/firmware updates in the meantime. If this is a known issue or you have any ideas as for what could have caused it, that would be greatly appreciated. 

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LabJack Support
LabJack Support's picture
Hello,

Hello,

If you are not on the most recent T7 firmware I would recommend upgrading and trying again. We identified and fixed some issues with stream mode in our newer firmware releases. As of now the most recent T7 firmware version is 1.0287.

If that does not work please let us know and we can assist you further.

_rednax_
_rednax_'s picture
When I try updating firmware

When I try updating firmware through Kipling, I get an error saying "Encountered an Error in step: checkNewFirmware, error Error: New firmware version does not reflect upgrade." The dowload looks like it's working and the progress bar works like it should, but at the very end it throws this error (I also tried power cycling, factory resetting and restarting Kipling). However, I've tried upgrading the firmware for this T7 in the past (if only to get rid of the notification button on Kipling), and the exact same thing has usually occured. Since it wasn't breaking anything I was doing I didn't worry about it, i.e. it's not a new issue. Also, if it helps, I'm using an OEM board and connecting through ethernet with a static IP. 

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LabJack Support
LabJack Support's picture
Start by removing all

Start by removing all connections to the T7 except for USB then try updating again.

If that does not work then I suspect that the flash memory has been damaged. Please use Kipling run the attached lua script. The script will dump the calibration data into the debug log. Copy the log and email it to [email protected]

 

 

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_rednax_
_rednax_'s picture
I actually figured out the

I actually figured out the problem, and luckily it isn't that the flash memory is damaged. My current setup is a bit convoluted, and the way I had it was that the connection was going desktop usb -> usb extender -> usb to ethernet adapter / triple usb hub combination -> microcontroller -> labjack power source (I can't just go from usb directly since the OEM board doesn't have a usb connector). This was working fine on my laptop, but recently I've started to do work from home and the current rating on my desktop usb must be different or something. When probing things with a multimeter I realized that the T7 was only getting 4 volts of power, enough to stay on but for some reason messing up streaming. By removing each individual component, I think the biggest drop was the microcontroller, where even though the pinout said usb source voltage (in this case 5V) it was only outputting ~4.3V. I switched to a seperate usb port for power, and now my program works fine. 

As an aside, even when I connected through usb, the firmware still fails in the same way. It's not affecting anything right now so I'm not really worrying about it, but I have had times where a newer version would be helpful. For example, being able to start up with a static ip by pulling pins to spc on startup. That being said, if it's not something you've seen before it's probably not worth the time to try and dig into what's causing a non-issue. 

Thanks for your help, I really appreciate it.