Arduino Nano circuit board (minimal) flaw, but why??

[ALonda]

As I looked over the circuit board layout for the arduino nano, I noticed... this;



All the pins are laid out in ascending-towards-usb-plug order, except RX and TX. For some reason they have been swapped. But swapping them made it necessary to add another via. What could possibly be the reason for this? Is it a copyright trap? Autorouter? I dont understand it, I see no sense in it.

/A

[Nusa]

It's open-source hardware. Anyone can make/modify/sell the design. The restrictions are duplicating trademarked labels that the "official" boards carry.

If I had to guess, the Nano, Micro, and Pro Mini inherited that pin order from the pin choice made on the Mini.

Why did the Mini make that choice? I don't really know, but my guess is it made layout to the serial header (which duplicated TX/RX pins) easier.

[amspire]

I have a Chinese Nano clone, and it has no vias anywhere near the Tx and Rx. I have Arduino Mini clones too and they have the same pin order, so it seems it is a design choice made for a range of Arduino boards to have tx and Rx in this order.