Freescale Semiconductor Demonstration Board for Freescale MC9S12XHY256 Microcontroller DEMO9S12XHY256 DEMO9S12XHY256 用户手册
产品代码
DEMO9S12XHY256
MC9S12XHY-Family Reference Manual, Rev. 1.04
Freescale Semiconductor
491
Chapter 15
Serial Peripheral Interface (S12SPIV5)
Serial Peripheral Interface (S12SPIV5)
15.1
Introduction
The SPI module allows a duplex, synchronous, serial communication between the MCU and peripheral
devices. Software can poll the SPI status flags or the SPI operation can be interrupt driven.
devices. Software can poll the SPI status flags or the SPI operation can be interrupt driven.
15.1.1
Glossary of Terms
15.1.2
Features
The SPI includes these distinctive features:
•
Master mode and slave mode
•
Selectable 8 or 16-bit transfer width
•
Bidirectional mode
•
Slave select output
•
Mode fault error flag with CPU interrupt capability
•
Double-buffered data register
•
Serial clock with programmable polarity and phase
•
Control of SPI operation during wait mode
15.1.3
Modes of Operation
The SPI functions in three modes: run, wait, and stop.
•
Run mode
This is the basic mode of operation.
•
Wait mode
SPI
Serial Peripheral Interface
SS
Slave Select
SCK
Serial Clock
MOSI
Master Output, Slave Input
MISO
Master Input, Slave Output
MOMI
Master Output, Master Input
SISO
Slave Input, Slave Output