Ethernet FeatherWing with Xenon - Serial 2

According to the documentation, Pin D4 is connected to nINTERRUPT on the FeatherWing.

However, D4 is also the TX pin for Serial 2 on the Xenon.

The link above does mention " …[1] These pins are connected via jumper pads on the bottom. You can cut these jumper traces and rewire them to a different pin on the Mesh device if the need arises.".

Let us say I connect nINTERRUPT to D6 instead. Will this work? What changes are needed in the code?

I would appreciate the community’s input.

Thanks in advance.

While you can physically move the pin by cutting the jumper pads and adding jumper wires, there is no way to change which pins Device OS uses as the interrupt pin. So it won’t work.

At some time in the future the Ethernet pins might be reconfigurable in Device OS, but they are not reconfigurable at this time.

Thank you @rickkas7.

Are you saying that using the EthernetWing will prevent the use of Serial2 on the Xenon?

That would be a very serious problem for me since the SoftSerial library does not yet work on mesh devices.

Please see:

That is correct. It’s not currently possible to Serial2 on the Xenon at the same time as the Ethernet FeatherWing.

Another option is to use an I2C or SPI UART like the SC16IS740. That does work on mesh devices.

1 Like

OK, thank you @rickkas7. I am just wondering why have the ability to use jumper wires if the OS will not support it …

I appreciate the link above and will check it as I am out of options …


What about D5 which is used as CS on the FeatherWing. Is this also hard-coded in the OS or can be changed?

This board is a wonderful addition, thank you. But, I can barely solder regular stuff :sweat_smile:

Is this board available for purchase already populated?

Would this work?

That should work. The SC16IS740/750/760 are basically the same chip but with more capabilities in the higher numbers. I’m pretty sure my library should work with the SC16IS750. And that’s a really good price for the breakout.

Perfect - THANK YOU.

Would this be the correct wiring?

Yes, though the library software doesn’t use the IRQ, so you can leave that unconnected.

1 Like

OK, thanks again.

Can D5 be reconfigured on the FeatherWing? (used as CS).

None of the Ethernet FeatherWing pins can be reconfigured because Device OS expects them to be on the pins they’re currently on. The ability to reconfigure the CS, reset, and INT pins will probably be added in a future release, but I don’t have a schedule for when that will happen.

I see. That completely prevents the use of Serial2 then on the Xenon. I was hoping that D5 can be reconfigured because it would have allowed the use of Serial2 on serial sensors that are only transmitting and do not need their RX connected …

If Serial 2 and the EthernetWing are not used at the same time, will it work? For example, turn the Ethernet off then on when needed …

In your description, you have:

6 >RST Can leave unconnected (red).

In the picture, you have it connected to 3V3.

Any preference?

Thanks again, I appreciate your help and time.