/*------------------------------------------------------------------*/
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/* --- STC 1T Series MCU Programme Demo ----------------------------*/
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/* 本程序经过测试完全正常, 不提供电话技术支持, 如不能理解, 请自行补充相关基础. */
/************* 本程序功能说明 **************
测试P4.4 P4.5 P4.6做IO输出方波。
****************************************************/
#include <reg51.h>
sfr P4 = 0xC0;
sfr P4SW = 0xBB;
sfr P4M1 = 0xB3; //P4M1.n,P4M0.n =00--->Standard, 01--->push-pull
sfr P4M0 = 0xB4; // =10--->pure input, 11--->open drain
sbit P44 = P4^4;
sbit P45 = P4^5;
sbit P46 = P4^6;
sbit P47 = P4^7;
void main(void)
{
unsigned int i;
P4SW |= (1<<4); //P4.4允许设置成IO
P4SW |= (1<<5); //P4.5允许设置成IO
P4SW |= (1<<6); //P4.6允许设置成IO
P4M1 &= ~(1<<4); //P4.4设置成准双向IO
P4M0 &= ~(1<<4);
P4M1 &= ~(1<<5); //P4.5设置成准双向IO
P4M0 &= ~(1<<5);
P4M1 &= ~(1<<6); //P4.6设置成准双向IO
P4M0 &= ~(1<<6);
// P4M1 &= ~(1<<7); //P4.7设置成PUSH-PULL 要在下在时指定RESET pin用做P4.7，并且使用外部晶体时钟
// P4M0 |= (1<<7);
while(1)
{
for(i=0; i<1000; i++) ; //延时
P44 = ~P44; //取反输出方波
P45 = ~P45;
P46 = ~P46;
// P47 = ~P47; //要在下载时指定RESET pin用做P4.7，并且使用外部晶体时钟
}
}
