Serial UART Communication

Ahh - thanks. I'll change that. For now, just do parity:0 (or leave it out). parity:null works for no parity too, as you suggest.

UART/USART are actually because of the STM32 chip that's being used. A USART has a CK (clock) pin, and a UART doesn't. There's no support for the CK pin in Espruino right now, so you can actually safely assume that both UART and USART are the same.

And with the pins - yes, on Espruino you've usually got a choice of which pin you put which peripheral on. However you can't put rx on one pin and tx on the other - both rx and tx have to be on pins 'next' to each other - eg . use B6+B7 or A9+A10, not B6+A10