Just bumping this to say I’ve added the serial transport mechanism to the note_c_hook so you can use the zephyr module with either i2c or serial now 
.
Depending on your Notecarrier (e.g. Notecarrier F), you may need to bridge F_TX → N_RX and F_RX → N_TX with a jumper and also ensure that the DFU switch is set to ‘NORMAL’.
// for example, using the usart0 bus
/ {
aliases {
notecard = &usart0;
};
};