You have a trio of footprints for the Seeed Xiao nRF52840, and a trio for the Xiao rp2040, which I'm sure are widely used - thank you.
This family has grown, see https://wiki.seeedstudio.com/SeeedStudio_XIAO_Series_Introduction/ or https://www.seeedstudio.com/xiao-series-page
The XIAO RP2350, XIAO MG24 (inc sense variant), XIAO nRF54L15 (inc sense variant), and XIAO RA4M1 seem to have adopted a consisently placed set of back pads exposing up to eight more GPIO pins. Some of these have bluetooth and may become popular for keyboards.
I'm currently more interested in the slightly older Seeed Studio XIAO nRF52840 Plus (which again has a sense variant) which exposes nine more GPIOs as tiny castellated points between the original pins (making 20 GPIO available):
9 extra 1.27mm pitch SMD castellation pins beyond standard XIAO nRF52840
The XIAO nRF52840 Plus was used in the VisorBearer PCB (also under the CERN-OHL-P-2.0 license), that footprint might be useful here?
You have a trio of footprints for the Seeed Xiao nRF52840, and a trio for the Xiao rp2040, which I'm sure are widely used - thank you.
This family has grown, see https://wiki.seeedstudio.com/SeeedStudio_XIAO_Series_Introduction/ or https://www.seeedstudio.com/xiao-series-page
The XIAO RP2350, XIAO MG24 (inc sense variant), XIAO nRF54L15 (inc sense variant), and XIAO RA4M1 seem to have adopted a consisently placed set of back pads exposing up to eight more GPIO pins. Some of these have bluetooth and may become popular for keyboards.
I'm currently more interested in the slightly older Seeed Studio XIAO nRF52840 Plus (which again has a sense variant) which exposes nine more GPIOs as tiny castellated points between the original pins (making 20 GPIO available):
The XIAO nRF52840 Plus was used in the VisorBearer PCB (also under the CERN-OHL-P-2.0 license), that footprint might be useful here?