Purchased XIAO, received FEMTO!


Not a new user; I’m using XIAOs since a few months.

Now I purchased (Amazon, as always) another set of 3 x XIAO for a new project.

The box is the same as before, sealed, with “Seeeduino XIAO” written on it.

But this time, they show up as “Seeeduino Femto”, not “XIAO”!

What’s happening? I’ve just read another user with similar problems (FEMTO board inside XIAO box).

Thanks for any suggestion

Hi XFer

Please go to Arduino IDE -> tool -> board -> Seeed SAMD board -> then select Seeeduino XIAO upload a program. the board info will be change to Seeeduino XIAO.

Best regards

It worked, thanks!

Oddly, it also changed the COM port number (from 11 to 9). Not an issue of course.

Now this is STRANGE…

If I select the destination board as FEMTO (that is, as received), the power draw when running a simple arithmetic sketch is 8.2 mA.
But if I select the destination board as XIAO, the power draw with the very same sketch clibs to 13.3 mA !

I’ve noticed that in boards.txt, compilation flags are different between the two boards.

For the FEMTO, a "-DCRYSTALLESS " is added to the XIAO flags.

What does it mean?

Why does it cause a (welcome) lower power consumption?

Hi Xfer

FEMTO and XIAO both have different pin connect with the microchip, the FEMTO board is used the micro-USB to connect the power supply, and the XIAO is using the type-c.
I recommend you only use XIAO, coz FEMTO has been stopped production.

Best regards

Yes but, as I said before, my boards showed up as FEMTO out-of-the-box, not XIAO!

Mine that just bought has usb-c and it shows FEMTO.