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Ensure to > > > > > > Do you means SCL have additional toggle? You capture waveform? > > > > > > > Yes exactly. We were able to capture the waveform when the issue > > happens. It doesn't always happen though, it depends on how much time > > passes between clearing MSTA and MTX and reading from I2DR. > > > > If you want to see the waveform, I uploaded it to our server: > > https://share.toradex.com/dwnhcrl6b9toib6 > > You can see the additional clock at the right end, after "0x17 + NAK". > > Have you had a chance to look at the waveform? Do you have any concerns > about the proposed solution? I am fine. Add carlos, who did many work about I2C. Frank > > Best regards, > Stefan