hello.c

ARM7_LPC21xx_UART proteus仿真和keil文件

#include <LPC21xx.H>
#define CR 0x0D
char ledDown[]={"The LED is down!\n"};
char ledUp[]={"The LED is up!\n"};
int putchar (int ch)  {                  /* 向串口输出一个字符 */
  if (ch == '\n')  {
    while (!(U1LSR & 0x20));
    U1THR = CR;
  }
  while (!(U1LSR & 0x20));
  return (U1THR = ch);
}
void delay (void)  {                         
  unsigned volatile long i,j;
  for(i=0;i<60000;i++)
  for(j=0;j<5;j++)
  ;
}
void serialPuts(char *p){                  /* 向串口输出字符串 */
  while (*p != '\0'){
  	putchar(*p++);
  }
}
int main (void)  {
  /* 开始初始化串口 */ 
  PINSEL0 = 0x00050000;           /* 设置引脚，开串口功能 */
  U1LCR = 0x83;                   /* 8位数据，无效验，一个停止位 */
  U1DLL = 97;                     /* VPB 15MHz的时候波特率为9600 */
  U1LCR = 0x03;                   /* DLAB = 0 */
  /* 结束初始化串口 */ 
  IO0DIR = 0x000001;						/*将P0.0设置为输出 */
  while (1)  {
  	IO0CLR = 0x000001;
	serialPuts(ledUp);
	delay();
  	IO0SET = 0x000001;
	serialPuts(ledDown);
	delay();
  }
}