Quote Originally Posted by HenrikOlsson View Post
What are the reasons for not using the USART pins but instead using some ordinary I/O pins for serial in and out?
Henrik,

Looks like I need to rephrase my previous response.

I had assumed PICAXE was using the hardware USART to download their program. While reading their user manual, I learned they are instead using SerIn/SerOut (i.e. software UART) for downloading and recommend leaving it free to avoid false triggers or interference with downloads. I will modify the ConnectOne and Tibbo shields, accordingly.