ad.c

该源码是创维特ARM7 JX44B0X板的例子程序

#include <stdio.h>
#include <sys/time.h>
#include <signal.h>
#include "../include/44b.h"

struct timeval tpstart;

#define MAX_VALUE                       0x3ff
#define MIN_VALUE                       0x0
                                                                                       
char display_buffer[6];
int refresh_index = 0;
                                                                                       
unsigned char seg7table[16] =
{
    /* 0       1       2       3       4       5       6      7*/
    0xc0,   0xf9,   0xa4,   0xb0,   0x99,   0x92,   0x82,   0xf8,
                                                                                       
    /* 8       9      A        B       C       D       E      F*/
    0x80,   0x90,   0x88,   0x83,   0xc6,   0xa1,   0x86,   0x8e,
};

void poll_timer(int signo)
{
    if(refresh_index == 2) refresh_index ++;
    if(refresh_index == 5) refresh_index =0;

    *((unsigned char*) 0x02000006) = 0x3f & ~(0x01 << refresh_index);
    *((unsigned char*) 0x02000004) = seg7table[display_buffer[refresh_index]];
    refresh_index ++;
}

void init_sigaction(void)
{
    struct sigaction act;
    act.sa_handler=poll_timer;
    act.sa_flags=0;
    sigemptyset(&act.sa_mask);
    sigaction(SIGPROF,&act,NULL);

    /* begin get the time */
    gettimeofday(&tpstart,NULL);
}

void init_time()
{
    struct itimerval value;
    value.it_value.tv_sec=0;
    value.it_value.tv_usec=1;
    value.it_interval=value.it_value;
    setitimer(ITIMER_PROF,&value,NULL);
}

char trans_input(int value)
{
    if(value == MAX_VALUE) return 50;

    return(char )(value * 50 / (MAX_VALUE-MIN_VALUE));
}
/*
 * timer application code
 * compile :
 *          $arm-elf-gcc -Wl,-elf2flt -o ad ad.c
 *          $cp ad /tftpboot/examples
 * run in target:
 *          #cd /var
 *          #ftp 192.168.1.180
 *          ftp>bin
 *          ftp>cd /tftpboot/examples
 *          ftp>get ad
 *          ftp>by 
 *          #./ad
 */
int main(int argc, char **argv)
{
    int loop_delay;
    int data = 0;
    int get_index;
 
    rCLKCON=0x7ff8;

    init_sigaction();
    init_time();
                                                                                       
    while(1)
    {
	        int value;
                int rADCDAT_TEMP0,rADCDAT_TEMP1,rADCDAT_TEMP2,rADCDAT_TEMP3,
                    rADCDAT_TEMP4,rADCDAT_TEMP5,rADCDAT_TEMP6,rADCDAT_TEMP7;
                                                                                       
                rADCPSR=0x0;
                                                                                       
                data = 0;
                                                                                       
                for(get_index = 0; get_index < 16; get_index++)
                {
                        rADCCON=0x1|(0x2<<2);   // AIN2
                        while(!(rADCCON & 0x40));
                        data+=rADCDAT;
                }
                                                                                       
                data /= 32;
                                                                                       
                value = trans_input(data);
                display_buffer[0] = value / 10;
                display_buffer[1] = value % 10;
                                                                                       
                data = 0;
                                                                                       
                for(get_index = 0; get_index < 16; get_index++)
                {
                        rADCCON=0x1|(0x3<<2);   // AIN3
                        while(!(rADCCON & 0x40));
                        data+=rADCDAT;
                }
                data /= 32;
                                                                                       
                value = trans_input(data);
                                                   
                display_buffer[3] = value / 10;
                display_buffer[4] = value % 10;
    }

    exit(0);
}