MC908QC16CDRE 参数 Datasheet PDF下载

Chapter 15

Serial Peripheral Interface (SPI) Module

15.1 Introduction

This section describes the serial peripheral interface (SPI) module, which allows full-duplex,

synchronous, serial communications with peripheral devices.

The SPI shares its pins with general-purpose input/output (I/O) port pins. See

for port location

of these shared pins.

15.2 Features

Features of the SPI module include:

• Full-duplex operation

• Master and slave modes

• Double-buffered operation with separate transmit and receive registers

• Four master mode frequencies (maximum = bus frequency

÷

2)

• Maximum slave mode frequency = bus frequency

• Serial clock with programmable polarity and phase

• Two separately enabled interrupts:

– SPRF (SPI receiver full)

– SPTE (SPI transmitter empty)

• Mode fault error flag with interrupt capability

• Overflow error flag with interrupt capability

• Programmable wired-OR mode

15.3 Functional Description

The SPI module allows full-duplex, synchronous, serial communication between the MCU and peripheral

devices, including other MCUs. Software can poll the SPI status flags or SPI operation can be interrupt

driven.

The following paragraphs describe the operation of the SPI module.

MC68HC908QC16 • MC68HC908QC8 • MC68HC908QC4 Data Sheet, Rev. 5

Freescale Semiconductor

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