DS90UB954-Q1: USB2ANY makes all I2C communications fail

Mathieu Ghetti

Part Number: DS90UB954-Q1
Other Parts Discussed in Thread: USB2ANY, ALP

I have run the MAP tool successfully on another platform now I am trying it on a new platform, I have the USB2ANY board plugged in (only SCL and SDA) and can see the I2C communications are fine but as soon as I open up the Analog Launchpad program all I2C communications fails and when I look at the oscilloscope the SDA line is pulled HIGH and SCL pulled LOW. Do you have any idea what the issue here could be?

Cheers,

Mathieu

over 3 years ago

0 Mathieu Ghetti over 3 years ago

Prodigy 30 points

Before Opening ALP After Opening ALP

0 Mathieu Ghetti over 3 years ago

Prodigy 30 points

A possible issue as well could be that the I2C bus on this platform does not allow for 2 Masters and if the TI board is master there may be an issue. Could someone confirm if the TI USB2ANY board is acting as Master or Slave?

0 Justin Phan over 3 years ago in reply to Mathieu Ghetti

TI__Mastermind 28240 points

Hi Matthieu,

It is possible to have multiple Masters on the UB954 I2C bus, but you would have to make sure each Master cooperates. The ALP will continuously send I2C read commands to read the registers in the UB954 device and update information in its GUI tabs. If other devices on the same I2C bus attempt to send any I2C commands, then that will conflict with ALP's operation and cause unexpected results.

ALP doesn't quite work well with other Masters on the I2C bus. In our labs, I tried running ALP on two different computers to the same UB954 EVM and the ALP software became unresponsive.

I would recommend making sure there are no other I2C commands being sent on the UB954 I2C bus. Make sure the only I2C commands come from ALP.

Best,

Justin Phan

0 Mathieu Ghetti over 3 years ago in reply to Justin Phan

Prodigy 30 points

Thankyou stopping all I2C communications on the bus except for the USB2ANY board has worked. I now have a related questions which I will start a new thread for. Thanks Again!

0 Justin Phan over 3 years ago in reply to Mathieu Ghetti

TI__Mastermind 28240 points

You are welcome. Glad to hear the issue is resolved.

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DS90UB954-Q1: USB2ANY makes all I2C communications fail