Data Sheet

2018/11/15 Particle Datasheets | Xenon datasheet
https://docs.particle.io/datasheets/mesh/xenon-datasheet/ 9/22
You can download a high resolution PDF version of the pin out here.
Pin Description
Li+ This pin is internally connected to the positive terminal of the LiPo battery connector.
VUSB This pin is internally connected to the USB (+ve) supply.
3V3 This pin is the output of the on-board 3.3V regulator.
GND System ground pin.
EN Device enable pin is internally pulled-up. To disable the device, connect this pin to GND.
RST Active-low system reset input. This pin is internally pulled-up.
MD This pin is internally connected to the MODE button. The MODE function is active-low.
RX Primarily used as UART RX, but can also be used as a digital GPIO.
TX Primarily used as UART TX, but can also be used as a digital GPIO.
SDA Primarily used as data pin for I2C, but can also be used as a digital GPIO.
SCL Primarily used as clock pin for I2C, but can also be used as a digital GPIO.
MO,MI,SCK These are the SPI interface pins, but can also be used as a digital GPIO.
Pin description