VL53L1X Internal state that cannot respond to the I2C communication start condition

[KArai.2]

Hello,

I am developing a system using VL53L1X.

Occasionally, when the host microcomputer is asynchronously reset, 

there is no response from the sensor after that.

It can be detected that the sensor's SDA is stuck at Low. We can handle it.

The situation I am encountering is that the sensor's SDA line is high, but I2C communication is not possible.

Is there an internal state that ignores the start condition from the host microcomputer?

If so, please tell me the transition conditions to that internal state.

Best regards.

[John E KVAM · Accepted solution]

From time to time, I've heard this complaint. It is almost always noice on the XShut line. That line appears to be on a hair-trigger. Even a small glitch causes the sensor to do a partial reboot - and that causes it to stop ranging. Put a big pull on that line - and a good sized cap and see if the the problem just doesnt go away.

Wouldn't hurt to check the ground as well. Noise is evil.

And if you say your are having I2C issues, it might not just be I2C.

But good job on seeing the bus-stuck-low. Lots of folks don't check that.

• john

[KArai.2]

Hello john-san,

Thank you for giving me interesting information.

If noise is the cause, it would be difficult to reproduce in a laboratory.

I will consider your advice.

I will make a proposal within my company to implement the advice you gave me.

Best regards.