红外遥控应用：深入解析C51单片机红外遥控协议，实现无线控制

# 1. 红外遥控基础

红外遥控是一种利用红外线进行无线通信的技术，广泛应用于电视、空调、音响等电子设备的远程控制。红外线是一种电磁波，其波长介于可见光和微波之间，具有穿透力强、方向性好、成本低廉等特点。

红外遥控系统主要由发射器和接收器组成。发射器将电信号转换成红外信号，通过红外发射管发出。接收器接收红外信号，将其转换成电信号，再由解码器解析出控制指令，控制设备执行相应操作。

# 2. C51单片机红外遥控协议

### 2.1 红外遥控协议概述

红外遥控协议是一种通过红外线传输指令的通信协议，广泛应用于电视机、空调、DVD等家用电器中。C51单片机红外遥控协议是一种基于C51单片机的红外遥控协议，它采用脉宽调制（PWM）技术，通过红外发射二极管（LED）发出不同频率和脉宽的红外信号，实现对设备的控制。

### 2.2 C51单片机红外遥控协议分析

#### 2.2.1 协议帧结构

C51单片机红外遥控协议帧结构如下图所示：

sequenceDiagram
participant A as 遥控器
participant B as 设备
A->B: 起始位（9ms低电平）
B->A: 应答位（4.5ms高电平）
A->B: 地址码（16bit）
A->B: 反码（16bit）
A->B: 数据码（8bit）
A->B: 停止位（4.5ms高电平）

* 起始位：9ms低电平，表示帧的开始。
* 应答位：4.5ms高电平，表示设备收到起始位并准备接收数据。
* 地址码：16bit，表示要控制的设备地址。
* 反码：16bit，是地址码的补码，用于校验地址码的正确性。
* 数据码：8bit，表示要发送的指令。
* 停止位：4.5ms高电平，表示帧的结束。

#### 2.2.2 协议参数

C51单片机红外遥控协议的参数如下表所示：

| 参数 | 值 |
|---|---|
| 载波频率 | 38kHz |
| 脉宽 | 1ms |
| 起始位时间 | 9ms |
| 应答位时间 | 4.5ms |
| 地址码长度 | 16bit |
| 数据码长度 | 8bit |
| 停止位时间 | 4.5ms |

#### 2.2.3 协议时序

C51单片机红外遥控协议时序如下图所示：

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