A serial peripheral interface (SPI) controller can be configured in response to data received via the interface. The SPI controller can perform read and write operations upon registers of a register bank in response to signals received via one or more of a data signal line, a clock signal line, and a select signal line. By detecting combinations of signals on one or more of the data signal line, clock signal line and select signal line, the SPI controller can detect the initiation of data read and write operations that may be in accordance with any of several different SPI protocols.