【ARM】ADC·FS2410數模轉換

開發環境

       一、硬件平臺：FS2410

       二、主機：Ubuntu 12.04

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ADC寄存器配置

      一、初始化ADC（ADCCON）

       設置預分頻，預分頻因子，選擇A/D轉換通道，並選擇正常模式且啓動轉換

      二、判斷轉換是否結束(ADCCON[5])

      三、讀取轉換結果（ADCDATn）

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串口的初始化

       見《串口通訊·FS2410》：http://infohacker.blog.51cto.com/6751239/1223137

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源代碼

      //adc.c

#include "2410addr.h"      //頭文件，包含寄存器的設置
                                      
void putc(char ch)      //發送字符
{
    while(!(rUTRSTAT0 & 0X2));    //判斷髮送緩衝區是否爲空
                                           
    rUTXH0 = ch;        //發送
}
                                      
char getc(void)       //接收字符
{
    while(!(rUTRSTAT0 & 0X1));     //判斷接收緩衝區是否爲空
                                          
    return rURXH0;      //接收
}
                                      
void putstr(char *str)      //發送字符串
{
    while(*str != '\0')
    {
        if(*str == '\n')
        {
            putc('\n');
            putc('\r');
        }
        else
            putc(*str);
                                              
        str++;
    }
}
                                      
void wait(long long max)      //延遲函數
{
    for(; max > 0; max--)
        ;
}
                                      
void itoa(unsigned long value)    //進行字符轉換
{ 
    unsigned long temp;
    int i, flag = 0;
    char data[4];
                                          
    for(i = 0; i < 4; i++)    //清空數組
        data[i] = '\0';
                                      
    for(i = 0; i < 3; i++)
    {
        temp = (value >> 4 * i) & 0xf;
                                              
        if(temp < 10)
            data[2 - i] = '0' + temp;
        else
        { 
            if(temp <= 0xf)
                data[2 - i] = 'a' + temp - 10;
        }
    }
                                      
    putstr(" Value of AIN0 is 0x");
    putstr(data);
                                          
    putstr("\r");
    putstr("\n");
}
                                      
int main(void)
{
    rGPHCON = rGPHCON & ~(0xf << 4) | (0xa << 4);    //配置RDX0與TDX0
    rGPHUP = 0X0c;     //設置上拉電阻
                                      
    rUFCON0 = 0;    //不用FIFO</span></span>
    rUMCON0 = 0;    //不用流控</span></span>
    rULCON0 = 0X3;  //8位數據，1箇中止位，無校驗，正常模式
    rUCON0 = 0X5;   //時鐘源位PCLK,中斷方式爲查詢
    rUBRDIV0 = ((int)(50000000 / 115200 / 16) - 1); //設置波特率爲115200
    rADCCON = 0x4c41;  //初始化ADC
                                      
    putstr("\nThis is ADC test:\n");
                                      
    unsigned long temp = 0;
                                          
    while(1)
    {
        while((rADCCON & (1 << 15)) == 0);     //判斷是否轉換結束
                                      
        temp = rADCDAT0;     //讀取轉換值
        itoa(temp);
                                              
        rADCCON = 0x4c41;     //再啓動ADC
        wait(200000);
    }
                                      
    return 0;
}

     //start.S

.text
.global _start
_start:
#define WATCHDOG 0x53000000
    ldr r0, =WATCHDOG
    mov r1, #0
    str r1, [r0]
                                  
    ldr sp, =1024*4
    bl main
                                  
loop:
    b loop

     //Makefile

adc.bin: start.S adc.c
    arm-linux-gcc -c start.S -o start.o
    arm-linux-gcc -c adc.c -o adc.o
    arm-linux-ld -Ttext 0x30008000 start.o adc.o -o adc
    arm-linux-objcopy -O binary -S adc adc.bin
                                
clean:
    rm -f *.o adc.bin

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編譯連接

     OK，成功！