Re : Reset I2C connection within LabVIEW

[ruud_unibw]

Hello,

For pressure measurements I have to following set-up:

1. pressure transducer

2. I2C connection with NI9402 plug-in card

3. NI9402 in NI9148-cDAQ

4. pressure values monitored with LabVIEW

In some cases the connection hangs-up and the pressure measurements stop. I do not know the reason for this matter. When I want to restart the measurement I have to disconnect and reconnect the I2C-cable which is connection with the pressure transducers. Then I can restart my measurements.

Unfortunately, during real experiments I do not have access to the pressure transducers, nor the NI9402 or NI9402. Thus I need to send some kind of reset bit with LabVIEW.

Thanks in advance,

Ruud

[JB]

You could try to reset the NI9402 by the use of this VI.

[ruud_unibw]

Thank you JB,

The connection problem occurs within the pressure transducers and not the NI9402 or NI9148-cDAQ.

Thus, the DAQmx Reset Device VI does not work because it needs an TRUE signal on the "error"-line.

--> Can I create an error by myself, so I can trigger the DAQmx Reset Device VI manually??

[JB]

Do you mean the "error in" wire of the VI ? The VI will execute even there is no error.

[mkais]

Hi ruud_unibw,

can you send us your VI?

[ruud_unibw]

Hi Kais Mekacher,

Problem

##########

At arbitrary moments the measurement stops. In this case, LabVIEW is still running without error, but all measurement values return to zero. It does not happen very often, but when it happens it is not possible to go into the room wherein the equipment is installed.

It does not help when the VI is started again. We found out, that after disconnecting/ reconnecting the connection with the pressure transducers itself (and a re-run of the VI) the measurement works again. For that reason I want to send some kind of "Reset" signal to the NI9402 or NI9148-cDAQ.

Sorry, it is not easy to explain the problem/ entire set-up.

FILES

#####
"HDI Sensoren" is the entire project.

"Host" is just the interface which is used during the experiment.

It that sufficient, or should I upload all files as ".zip"

Thanks in advance,

Ruud

[FrankLp]

Hi Ruud,

In order to look at your issue , we need all of your files. Just the project file and the host VI isn't sufficent to pinpoint you to a possible solution.

You said , that you're using the I2C Bus to communicate and if you remove and replug the card an restart the VI, the application works again. This could indicate an issue with the I2C Bus communication. Have you tried to reinitiate the I2C Bus Communication?

Regards,

Frank

[ruud_unibw]

Hello,

This is the entire project.

In the case problem occurs, I have only two solutions:

- de/ re-connect the I2C connection with the pressure transducers

- de/ re-connect the electricity cable to the I2C wire (5 Volt, 550mA)

It does not work when I plug out the NI9402 card, but

as soon as I plug in the cable to the pressure transducers or the electricity cable.. the measurement can be continued immediatly.

@Frank, how can I reinitiate the I2C bus communication?

Greetings, Ruud

[ruud_unibw]

the entire project as ".zip"

[FrankLp]

Hi Ruud,

are you getting any error messages when the connection crashes?

Regards,

Frank