Spi rx-fifio-flush

Hello,

i want to sent 3 messages via SPI without reception.
After that i want to send messages and use the recepted Data.

My idea is, to implement the SPI without Fifo receive interrupt first.
After that i Flush the RX-FIFO an activate the interrupt.

Now the problem:
Is there any flag, which indicates the running of the SPI transmit?
I have no interrupt to reset the standard events.

After the RX-flush, it is possible that the SPI get new Data, which are just shifting out.

Best regards