Same code working differently on Nano 33 IoT and Mega

Official Hardware Nano Family Nano 33 IoT
12

Thanks @Klaus_K, thankfully I have an oscilloscope :slight_smile:

@ademmler these are the readings from my oscilloscope:

Nano 33 IoT Clock:

DS1Z_QuickPrint1
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Nano 33 IoT Data

DS1Z_QuickPrint2
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The data signal does not look like it's changing but the readings on the serial monitor are looking like my original post. The only thing that was changing was the spikes going below the 0V. Are toes supposed to be there, are those the data signals?

Meanwhile these are the readings with same code and circuit, but using an Arduino Mega instead of the Nano 33 IoT..

Mega SCL:

DS1Z_QuickPrint9
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Mega SDA:

DS1Z_QuickPrint8
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The differences I have seen from the two boards is that the Mega goes up to 5v and the Nano 33 to 3v, and that the peaks going under 0V on the Mega are maybe slightly smaller.

The Mega readings on the serial monitor are good too.

All seem good right?