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U3 Generic Help

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Helait
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U3 Generic Help
I had attached a pdf file .....
LabJack Support
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Take a look at the LabJack U3

Take a look at the LabJack U3 quickstart here:

https://labjack.com/support/quickstart/u3

For further help, please provide more details on what you need help with.

Helait
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I had attached a pdf file ...
I had attached a pdf file .....
LabJack Support
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When you post on this forum,

When you post on this forum, you will not see your post until we approve it.  That's how we keep spam off the forum.

 

LabJack Support
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Try posting your pdf now. It

Try posting your pdf now. It wasn't an allowable file type when you first posted, but it is now. Also, I removed some of your previous repeat and test posts.

Helait
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I upload a PDF file......

I upload a PDF file......

LabJack Support
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It looks like you are using

It looks like you are using stream mode.  Read the following to make sure you do indeed want to use stream mode:

https://labjack.com/support/datasheets/u3/operation

 

I suggest you use the Test panel in LJControlPanel for your initial troubleshooting and testing of the U3 and your signals.  Use known software so you don't have the added confusion of your own software.

 

 

1) Temperature:
With the same conversion formula I do not read the same values between the
application of Labjack and mine;
The temperature fluctuates by +/‐ 1.3 ° C;
I should get a fixed temperature to the tenth of a degree and see the increase or
decrease with a tenth of a degree.

So you are trying to read from 2x PT100 RTDs.  You have them connected to an LJTick-Resistance-1k that is plugged into AIN2/AIN3.

Do you have a U3-HV or U3-LV?  You want to use low voltage analog inputs with the LJTR, so if U3-LV then FIO2/FIO3 is fine, but if U3-HV you want to use a low voltage analog input on FIO or EIO:

https://labjack.com/support/datasheets/u3/hardware-description/ain

See "Resolution" here:

https://labjack.com/support/datasheets/accessories/ljtick-resistance

The math in that example works out to 0.76 degrees C per count, so that is the best you can expect for resolution.

 

2) Status of digital inputs
Get a reliable reading to operate accordingly.

In your stream I just see you adding 18 analog inputs (AIN0-AIN17).  Use the special channel numbers 193 and 194 to get digital inputs:

https://labjack.com/support/datasheets/u3/operation/stream-mode/digital-inputs-timers-counters

 

Helait
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Ok. one thing at a time.
Ok. one thing at a time.
Input stream configuration as follows:  

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.CLEAR_STREAM_CHANNELS, 0, 0, 0, 0)

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 0, 0, 0, 0)     'AIN0

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 1, 0, 0, 0)     'AIN1

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 2, 0, 0, 0)     'AIN2

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 3, 0, 0, 0)     'AIN3

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 4, 0, 0, 0)     'FIO4

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 5, 0, 0, 0)     'FIO5

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 6, 0, 0, 0)     'FIO6

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 7, 0, 0, 0)     'FIO7

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 8, 0, 0, 0)     'EIO0

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 9, 0, 0, 0)     'EIO1

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 10, 0, 0, 0)    'EIO2

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 11, 0, 0, 0)    'EIO3

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 12, 0, 0, 0)    'EIO4

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 13, 0, 0, 0)    'EIO5

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 14, 0, 0, 0)    'EIO6

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 15, 0, 0, 0)    'EIO7

So configured its ok.
When I add the instructions for CIO0 and CIO1

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.CLEAR_STREAM_CHANNELS, 0, 0, 0, 0)

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 0, 0, 0, 0)     'AIN0

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 1, 0, 0, 0)     'AIN1

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 2, 0, 0, 0)     'AIN2

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 3, 0, 0, 0)     'AIN3

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 4, 0, 0, 0)     'FIO4

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 5, 0, 0, 0)     'FIO5

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 6, 0, 0, 0)     'FIO6

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 7, 0, 0, 0)     'FIO7

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 8, 0, 0, 0)     'EIO0

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 9, 0, 0, 0)     'EIO1

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 10, 0, 0, 0)    'EIO2

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 11, 0, 0, 0)    'EIO3

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 12, 0, 0, 0)    'EIO4

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 13, 0, 0, 0)    'EIO5

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 14, 0, 0, 0)    'EIO6

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 15, 0, 0, 0)    'EIO7

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 16, 0, 0, 0)    'CIO0

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 17, 0, 0, 0)    'CIO1

So configured by an error message:
UNABLE TO CONFIGURE STREAM.   What's wrong?
LabJack Support
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Those are all analog inputs. 

Those are all analog inputs.  When you say channel 11, for example, that means an analog input reading from AIN11 which is the same as EIO3:

https://labjack.com/support/datasheets/u3/hardware-description/fio

For analog input readings you use channel numbers 0-15.  For digital input readings in stream mode you use the special channel numbers 193 and 194:

https://labjack.com/support/datasheets/u3/operation/stream-mode/digital-inputs-timers-counters

I propose this is what you want:

                LJUD.AddRequest(u3.ljhandle, LJUD.IO.CLEAR_STREAM_CHANNELS, 0, 0, 0, 0)
                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 0, 0, 0, 0)     'AIN0 - Torque A
                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 1, 0, 0, 0)     'AIN1 - Torque B
                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 4, 0, 0, 0)     'AIN4/FIO4 - LJTRA
                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 5, 0, 0, 0)     'AIN5/FIO5 - LJTRB
                LJUD.AddRequest(u3.ljhandle, LJUD.IO.ADD_STREAM_CHANNEL, 194, 0, 0, 0)     'CIO0-CIO3
 

The value returned by 194 will have the states of CIO0-CIO3 in the lowest 4 bits.