You should always specify the pins for uart/i2c/spi/etc before you try to use the interface in question. I think in most cases (certainly in some), the interfaces are not pointed at any pins by default (and/or the pins aren't pointed at the interfaces) until you call setup and specify pins.
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Nice! Glad it's working.
You should always specify the pins for uart/i2c/spi/etc before you try to use the interface in question. I think in most cases (certainly in some), the interfaces are not pointed at any pins by default (and/or the pins aren't pointed at the interfaces) until you call setup and specify pins.