Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Microchip Technology/ATSAMV71J20/USART0/US_LONL2HDR#0x0
LON L2HDR Register
LON Backlog Increment
LON Alternate Path Bit
LON Priority Bit
https://github.com/cmsis-svd/cmsis-svd-data