MCCIRM Freescale Semiconductor / Motorola, MCCIRM Datasheet - Page 43

• Manufacturer Part Number: MCCIRM
• Description: MCCIRM Multi-Channel Communications Interface Reference Manual
• Manufacturer: Freescale Semiconductor / Motorola

4.4 SPI Pins
4.5 Operating Modes
4.5.1 Master Mode
Multichannel Communication Interface — Rev. 1.0
MOTOROLA
The SPI uses four bidirectional pins. These pins may be configured for
general-purpose I/O when not needed for the SPI.
pins and their functions. Refer to
additional information.
The SPI operates in either master or slave mode. Master mode is used
when the MCU originates data transfers. Slave mode is used when an
external device initiates serial transfers to the MCU. The MSTR bit in
SPCR selects master or slave operation.
Setting the MSTR bit in SPCR selects master mode operation. In master
mode, the SPI can initiate serial transfers but cannot respond to
externally initiated transfers. When the slave-select input of a device
configured for master mode is asserted, a mode fault occurs.
Master in/slave out (MISO)
Master out/slave in (MOSI)
Serial clock (SCK)
Slave select (SS)
Freescale Semiconductor, Inc.
For More Information On This Product,
Pin Name
Go to: www.freescale.com
SPI Submodule
Table 4-2. SPI Pin Function
Master
Slave
Master
Slave
Master
Slave
Master
Slave
Mode
Section 2. Signal Descriptions
Provides serial data input to the SPI
Provides serial data output from the SPI
Provides serial output from the SPI
Provides serial input to the SPI
Provides clock output from the SPI
Provides clock input to the SPI
Detects bus-master mode fault
Selects the SPI for an
externally initiated serial transfer
Function
Table 4-2
Reference Manual
SPI Submodule
shows SPI
SPI Pins
for
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