Use with seeed xiao rp2040

[thomas-watters-skydio]

ref: Seeed-Studio-XIAO-RP2040-v1.3.pdf

I was able to get usb_device to work on the XIAO RP2040 with

default PIO_USB_DP_PIN_DEFAULT = 0, using J2.7 -> D+ and J4.1 -> D- (GPIO0, GPIO1),

also was able to get it to work with

PIO_USB_DP_PIN_DEFAULT = 28 J2.3 -> D+ and J2.4 -> D- (GPIO28, GPIO29),

but I couldn't get it to work with

PIO_USB_DP_PIN_DEFAULT = 3 J4.4 -> D+ and J4.3 -> D- (GPIO3, GPIO4)

any ideas, does the DP+ have to be on an "even" pin?

[thomas-watters-skydio]

i have a 1.56k pull-up between D+ and +3.3V (J4.5)