Can I use the rx/tx pins on a standard ethernet shield?

Projects General Guidance
1

I'm using an unofficial one from Ebay with no io-ref pin.

2

anyone?

3

Yes, you can use them. The Ethernet Shield does not use the pin 0 (RX) or pin 1 (TX) of the board below it. However, the Arduino Uno uses RX and TX to upload a sketch and for the serial monitor.

Do you have a compatible Ethernet Shield with W5100 chip that is not version 'R3' ?
That may not work with every Arduino board.
An Arduino board R2 will work with Ethernet Shield R2.
An Arduino board R3 will work with Ethernet Shield R3.

If you buy some cheap clones on Ebay, buy the 'R3' version. And don't forget to donate : https://www.arduino.cc/en/Main/Donate

4

thanks!

5

anyone?

I've got ebay w5100 shields and the serial pins work just fine.