Motorola MPC8260 - Manual (Page 929)

MOTOROLA Chapter 33. Serial Peripheral Interface (SPI) 33-5
Part IV. Communications Processor Module
drivers of SPI signals. The core must clear SPMODE[EN] before the SPI is used again.
After correcting the problems, clear SPIE[MME] and reenable the SPI.
Figure 33-3. Multimaster Configuration
SPIMISO
SPIMOSI
SELOUT0
SPISEL
SPICLK
SELOUT3
SELOUT1
SPI #2
SPIMISO
SPIMOSI
MPC8260
SELOUT1
SPISEL
SPICLK
SELOUT3
SELOUT2
SPIMISO
SPIMOSI
SPI #1
SELOUT0
SPISEL
SPICLK
SELOUT3
SELOUT2
SPI #0
Notes:
¥ All signals are open-drain
¥ For a system with more than two masters, SPISEL and SPIE[MME] do not detect all possible conflicts
¥ It is the responsibility of software to arbitrate for the SPI bus (with token passing, for example)
¥ SELOUTx signals are implemented in software with general-purpose I/O signals
SPISEL1 SPISEL0 SPISEL3 SPISEL2
SPIMISO
SPIMOSI
SELOUT0
SPISEL
SPICLK
SELOUT2
SELOUT1
SPI #3
MPC8260
MPC8260
MPC8260