Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32f1/STM32F101/CAN1/MCR#0x0
master control register
INRQ
SLEEP
TXFP
RFLM
NART
AWUM
ABOM
TTCM
RESET
DBF
https://github.com/modm-io/cmsis-svd-stm32