Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Keil/AT32F415xx_v2/SPI1/STS#0x0
status register
Receive data buffer full
Transmit data buffer empty
Audio channel state
Transmitter underload error
CRC calculation error
Master mode error
Receiver overflow error
Busy flag
https://github.com/cmsis-svd/cmsis-svd-data