单片机应用技术（经典项目化案例式新形态活页教材）第5版 课件 p25-2.1 8051的信号引脚

2.18051的信号引脚《单片机应用技术（C语言版）》深圳职业技术学院12345678910111213141516171819204039383736353433323130292827262524232221VCCGND电源引脚接入单片机的工作电源VCC（40）：接+5V电源GND（20）：接地12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0P0口（39～32）：P0.0～P0.7引脚P1口（1～8）：P1.0～P1.7引脚P2口（21～28）：P2.0～P2.7引脚P3口（10～17）：P3.0～P3.7引脚12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0XTAL2XTAL1RSTRST（9）：Reset，复位信号XTAL1（19）：片内振荡器的反相放大器和外部时钟发生器的输入端XTAL2（18）：片内振荡器的反相放大器和外部时钟发生器的输出端12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0XTAL2XTAL1RSTEAALEPSENPSEN（29）：外部程序存储器读选通信号，低电平有效。ALE（30）：地址锁存控制信号EA（31）：访问程序存储控制信号，通常接高电平。引脚名称引脚功能P0.0～P0.7P0口8位双向端口线P1.0～P1.7P1口8位双向端口线P2.0～P2.7P2口8位双向端口线P3.0～P3.7P3口8位双向端口线ALE地址锁存控制信号外部程序存储器读选通信号访问程序存储控制信号RST复位信号XTAL1和XTAL2外接晶体引线端VCC＋5V电源VSS地线12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0XTAL2XTAL1RSTEAALEPSENRXD/TXD/INT0/INT1/T0/T1/WR/RD/第一功能第二功能第二功能信号名称P3.0RXD串行数据接收P3.1TXD串行数据发送P3.2外部中断0申请P3.3外部中断1申请P3.4T0定时/计数器0的外部输入P3.5T1定时/计数器1的外部输入P3.6外部RAM或外部I/O写选通P3.7外部RAM或外部I/O读选通P3口各引脚的第二功能12345678910111213141516171819204039383736353433323130292827262524232221VCCGNDP1.0P1.1P1.2P1.3P1.4P1.5P1.6P1.7P0.0P0.1P0.2P0.3P0.4P0.5P0.6P0.7P3.0P3.1P3.2P3.3P3.4P3.5P3.6P3.7P2.7P2.6P2.5P2.4P2.3P2.2P2.1P2.0XTAL2XTAL1RSTEAALEPSENRXD/TXD/INT0/INT1/T0/T1/WR/R