Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32L0x2/SPI1/SR#0x0
status register
Receive buffer not empty
Transmit buffer empty
Channel side
Underrun flag
CRC error flag
Mode fault
Overrun flag
Busy flag
TI frame format error
https://github.com/cmsis-svd/cmsis-svd-data