• Thanks for the tips. I went through the DS3231.js source and see nothing fundamentally different as compared to my test script.

    The situation remains at complete power down - power up. This puts the DS3231 in a known state. The 'init()' runs after 2 seconds, eliminating any power upt timing issues.

    I'm quiet experienced with I2C communications and added the usual generate-clock-until-SDA-high, followed by an I2C Stop. This puts any connected I2C device in a bus-free state. The next 'readFrom()' will/should then generate the I2C start for each transfer, does it not ?

    Anyhow, the thing I still do not understand is the lack of pulses on either SDA or SCL on the oscilloscope at B6 and B7.


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