MCF51CN128 Reference Manual, Rev. 6
Freescale Semiconductor
14-1
Chapter 14
Serial Peripheral Interface (SPI)
14.1
Introduction
The serial peripheral interface (SPI) module provides for full-duplex, synchronous, serial communication
between the MCU and peripheral devices. These peripheral devices can include other microcontrollers,
analog-to-digital converters, shift registers, sensors, memories, etc.
The SPI runs at a baud rate up to the bus clock divided by two in master mode and up to the bus clock
divided by 4 in slave mode. Software can poll the status flags, or SPI operation can be interrupt driven.
NOTE
•
MCF51CN128 series devices do not include stop1 low-power mode.
Ignore references to stop1 in this chapter.
•
Use pin mux control registers from
Section 2.3, “Pin Mux Controls
” to
assign SPI signals to the MCF51CN128 package pins.
•
Most pin functions default to GPIO and must be software configured
before using SPI.
