Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32f3/STM32F303/ADC1/SMPR1#0x0
sample time register 1
SMP1
SMP2
SMP3
SMP4
SMP5
SMP6
SMP7
SMP8
SMP9
https://github.com/modm-io/cmsis-svd-stm32