The SPI Status Register (S0SPSR) contains read-only bits that are used to monitor the status of the SPI interface, including normal functions, and exception conditions. The primary purpose of this register is to detect completion of a data transfer. This is indicated by the SPI Interrupt Flag (SPIF) in the S0SPINT register. The remaining bits in the register are exception condition indicators. These exceptions will be described later in this section.
Ich würde mal sagen, dass das die Lösung deines Problems ist.
Quelle:http://www.nxp.com/documents/user_manual/UM10360.pdf
Seite 413.
Gruß Jannis