USB 8451 for I2C

[smercurio_fc · Accepted solution]

A framing error is generated by the UART on your computer's motherboard. It's typically a hardware issue or a mismatch in serial settings. Search the NI site for framing error and you'll find lots of hits, as this problem comes up often.

[vamshikrishna]

Is there any NI modules which contains analog measurements and digital measurements and frequency and also main I2C communication in one module???

Please give a suggesion if any third party modules also including above parameters.

[GerdW]

Hi vam,

please stop creating double/multple post for the very same question!

[mnpompili]

Hello to you all,

I use a usb 8451 to get measurements from a kinetic sensor (mpu 9150) but I have a problem of delaying in displaying and writing data.

I acquire data using ports SDA and SCL of the 8451 device. To make sure that it worked properly I've made a simple experiment.

I attached my sensor to a audio amplifier controlled by my computer. That means that i'me able to send tones to this amplifier, and my vi on labview displays the data on live.

However i observed a delay in displaying and writing the data, and this delay increases during the experiment. This is a graph which shows the evolution of this delay (it exponentionnaly rises)

Do you think that the problem comes from the 8451 device or my labview vi ?

thanks for your answers

[elcalverado]

Can you give some more information on what this graph is showing? Is that the delay between sending tones to the amplifier and when it is displayed to the front panel and written to your file?

Also, can you post your code here?

[mnpompili]

It is exactly that. The x-axis shows when we send the tones to the amplifiers (expressed in seconds), and the y-axis shows the delay between the tones and the displaying/writing (also in seconds). I've made another where I send a tone after one hour, and you can gess that I never received any feedback from this system (even after waiting several hours).

This is the code, I'd be very grateful if could take a look at it.

Thank you very much for your help

[elcalverado]

Nothing in the code stands out to me as a cause for concern. Have you tried using debugging tools to narrow down where in the code the delay is occurring?