108c5b34598e001b12e6fefcb3cfc8f8

基于Nios II的串口通信

/*
 * "Hello World" example.
 *
 * This example prints 'Hello from Nios II' to the STDOUT stream. It runs on
 * the Nios II 'standard', 'full_featured', 'fast', and 'low_cost' example
 * designs. It runs with or without the MicroC/OS-II RTOS and requires a STDOUT
 * device in your system's hardware.
 * The memory footprint of this hosted application is ~69 kbytes by default
 * using the standard reference design.
 *
 * For a reduced footprint version of this template, and an explanation of how
 * to reduce the memory footprint for a given application, see the
 * "small_hello_world" template.
 *
 */

#include <stdio.h>
#include <excalibur.h>
#include "system.h"
#include "altera_avalon_pio_regs.h"
#include "alt_types.h"


void delay()
{
  int i=0;
  while(i<10000)
   i++;
}

int main(void)
{
  unsigned char c;
  int ctrl;
  int d;
  int i,j;
  
  while(1)  
  {
  ctrl=IORD_ALTERA_AVALON_PIO_DATA(CTRL_PIO_BASE); //读取外接控制信号
  i=0;j=0;
  if(ctrl = 0)
  {
   IOWR_ALTERA_AVALON_PIO_DATA(LED_PIO_BASE,0x8);
  }
  if (ctrl=1)
  {
    j++;
    IOWR_ALTERA_AVALON_PIO_DATA(LED_PIO_BASE,0x7);
    while ((c=nr_uart_rxchar(na_uart)) == -1);  
      //从串口1接收字符
    if(c=0x55)
       nr_uart_txchar(0x33,0);
       delay();
     //将0x33传给默认串口
       {
        if ( c=0xaa )
        delay(); 
       //d=c&00FF;
       d=int(c/2);
       nr_uart_txchar(d,0);//将计算后的数据传给默认串口
       }
   else
      nr_uart_txchar(0xFF,0);
  }
  }
}