Datasheet

06 February 2012 Broadcom Europe Ltd. 406 Science Park Milton Road Cambridge CB4 0WW Page 149
© 2012 Broadcom Corporation. All rights reserved
Figure 10-2 SPI Cycle
Figure 10-3 Different Clock Polarity/Phase
10.2.2 Bidirectional mode
In bidirectional SPI master mode the same SPI standard is implemented except that a single
wire is used for the data (MIMO) instead of the two as in standard mode (MISO and MOSI).
Bidirectional mode is used in a similar way to standard mode, the only difference is that
before attempting to read data from the slave, you must set the read enable (SPI_REN) bit in
the SPI control and status register (SPI_CS). This will turn the bus around, and when you
write to the SPI_FIFO register (with junk) a read transaction will take place on the bus, and
the read data will appear in the FIFO.
Figure 10-4 Bidirectional SPI Master Typical Usage