LJTick-DAC with python (U3-LV) | LabJack
 

LJTick-DAC with python (U3-LV)

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ycyeh
Yuan-Chen Yeh's picture
LJTick-DAC with python (U3-LV)

Hi,

 

I was trying this code from Github :   https://github.com/labjack/LabJackPython/blob/master/Examples/ljTickDacS...

I connected my LJTick to VS/GND/FIO4/FIO5 and was trying to read the output at FIO6 and also I set dev.configIO(FIOAnalog = 112)

I ran the code and but it gave me this error "I2C_BUS_BUSY (116)" how should I fix this?

LabJack Support
LabJack Support's picture
The lines you connect your

The lines you connect your LJTick-DAC to need to be configured as digital I/O, and you configured them as analog inputs when setting FIOAnalog to 112 (b01110000) which will cause the error you are seeing. Instead use this configIO to set FIO6 as analog and the reset of the FIOs to digital I/O, and see if that helps:

dev.configIO(FIOAnalog = 64)  # 64 = b01000000

ycyeh
Yuan-Chen Yeh's picture
Thanks, it works now, but it

Thanks, it works now, but it seems that the FIO can only read up to 2.5V? Is there any way I can measure a higher voltage (~10V)?

LabJack Support
LabJack Support's picture
With the U3-LV, no it does

With the U3-LV, no it does not have a range to measure 10V. The U3-HV can measure +/-10V (or special range -10 to 20V) on its HV lines AIN0-AIN3.

For the U3-LV, with the special range you can measure 0 to 3.6 volts at highest. Refer to here on how to do that with negative channel 32:

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

We have a section here on signal voltages beyond 0 to 2.44V:

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

ycyeh
Yuan-Chen Yeh's picture
Hi, I have a follow-up

Hi, I have a follow-up question: what is the precision of the voltage output for LJTick-DAC? How can I specify it in the code here ?

https://github.com/labjack/LabJackPython/blob/master/Examples/ljTickDacS...

LabJack Support
LabJack Support's picture
The LJTick-DAC has 14-bits

The LJTick-DAC has 14-bits resolution. There is a specifications section here with details like that:

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

There are no precision related settings. You just set the DACs on the LJTick-DAC with I2C as demonstrated in the examples.