汇编语言 SPI/I2C 接口的时序控制与数据传输技巧

汇编语言SPI/I2C接口时序控制与数据传输技巧

在嵌入式系统中，SPI（串行外设接口）和I2C（两线式串行接口）是两种常用的通信协议，它们在数据传输速度、接口复杂度和系统资源占用等方面各有特点。本文将围绕汇编语言对SPI/I2C接口的时序控制与数据传输技巧进行探讨，旨在帮助读者深入理解这两种接口的工作原理，并掌握在汇编语言中实现它们的方法。

SPI接口时序控制与数据传输

1. SPI接口概述

SPI（Serial Peripheral Interface）是一种高速的、全双工、同步的通信接口。它由主设备（Master）和从设备（Slave）组成，主设备负责发起通信，从设备响应主设备的请求。

2. SPI接口时序控制

SPI接口的时序控制主要涉及时钟（SCLK）、数据输入（MOSI）、数据输出（MISO）和片选（CS）等信号。以下是一个简单的SPI时序图：

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