Understanding the reasoning in the "Adding More SERCOM Ports"-tutorial

Community Chit Chat
1

Hi there,

I’m reading my through the excellent tutorial about how to add yet a serial-port:

https://learn.sparkfun.com/tutorials/ad … boards/all

However, I have some difficulties understanding the logic in the section “Adding a UART”->“1.) Figure Out Which Pins to Use.”:

Let’s use D2 and see if we can put our new serial port right next to the original one. That means that RX should be on D3.

The choice of D2 for the TX is clear (if I understand it correct, and D4 could just as well have been used).

But the “obvious” next choice: “RX should be on D3”, I don’t follow.

Couldn’t we just as well have taken D38, D4 or D5?

(Any of the unused pins in the sercom 2 row in the chart: https://learn.sparkfun.com/tutorials/ad … ful-charts)

BR,

Egholm

2

You probably could use those pins, but the idea was replicating the same “pair” as pins D0 & D1. Since D2 & D3 are right there it’ll look exactly the same as D0 & D1. It was mostly asthetic. Feel free to leave a comment asking the original author if you would like as well.

3

Hi Brandon,

Ahaaa. Thanks for clarifying… I guess you could be right about that.

I might drop the question in article comments just to be sure, though :slight_smile:

Thanks for the quick answer!

Egholm