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JonnyMac wrote: »
Note: The circuit diagram shows a 2.2K resistor in the serial path. I tend to use 3.3K or higher with 5v inputs. The Activity Board uses 3.9K (limits current through pin protection diodes to 50% of max rating). I would suggest changing that to 4.7K as it's a common value that experimenters tend to have in their kits.