I2C decoding concern

I2C decoding here looks spot on:

I2C decoding on the 2nd I2C peripheral looks incorrect. Take a look at how its interpreting the bits of the address incorrectly, the first data byte incorrectly, and the ACK/NACK wrong. And the up-arrows on the SCL rising edges are missing? Maybe I’m missing something - it’s been a long day. :smiley:

This is running 2.3.34 with a Logic Pro 16.


Hi Mike,

Sorry to hear about this! Based on the image you shared, I suspect there may be glitches present in your SCL line (I notice a think rising edge in your SCL signal). Glitches will cause the analyzer to think there are multiple rising edges, which causes decoding errors.
Screen Shot 2021-08-23 at 5.43.31 PM

Can you try implementing a glitch filter as per the instructions below in your next capture?

The up arrows missing are strange though. Once you try out the glitch filter, and if you’re still seeing issues, would you mind doing the following?

Looking forward to hearing back!

Mike - thanks for the quick response!

I downloaded 2.3.35 and enabled 100 nsec of glitch filtering. No decoding issues seen since and up/down arrows are being displayed again on the SCL signal.

I really love being able to enable analog mode too to see what’s going on. Great feature and good eye noticing those double edges!



Example of things looking good again:

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