e03552d8845b001d19d1b339131f9a4e

altera DE1 SD_CARD带写入一个扇区功能的程序

/*
 * "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 <unistd.h>
#include "system.h"

#define clk *(unsigned int*)PIO_CLK_BASE
#define dat *(unsigned int*)PIO_DATA_BASE
int main()
{
  printf("Hello from Nios II!\n");
    int i,reg;
    dat=1;
    clk=1;
    (&dat)[1]=0;
    while(1)
    {
        reg=0;
        clk=1;
        clk=0;
        usleep(30);
        clk=1;
        usleep(30);
        for(i=0;i<8;i++)
        {
            clk=0;
            reg>>=1;
            if(dat) reg+=0x80;
            usleep(30);
            clk=1;
            usleep(30);
        }
        clk=0;
        usleep(30);
        clk=1;
        usleep(30);
        clk=0;
        usleep(110);
        clk=1;
//        usleep(30);
//        clk=0;
//        usleep(100);
//        clk=1;
        if(reg!=0xff)
        printf("%x\n",reg);
        usleep(100);   
    }
  return 0;
}