So I have some code that relies on SDA SCL for some timing, and I also want to use an external RTC clock (DS3231). Is there any way to use both? They both want to use pins 20 and 21.

Multiple items on SDA/SCL pins? Mega 2560

anon35827816 September 24, 2021, 7:26am 4

Then move the unnamed/mystery non-I2C application to a different pair of pins. You've got a Mega, so plenty of pins to choose from.

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