模數(shù)轉(zhuǎn)換與模擬比較-avr ad范例

AVR模數(shù)(AD)轉(zhuǎn)換范例程本范例使用 版本開(kāi)本程序簡(jiǎn)單的示范了如何使用ATMEGA16的ADC模數(shù)轉(zhuǎn)換器 查詢方 數(shù)據(jù)格式的變換出于簡(jiǎn)化程序考慮，各種數(shù)據(jù)有對(duì)外輸出，學(xué)習(xí)時(shí)建議使用JTAGICE硬件仿真電路圖設(shè)計(jì)為簡(jiǎn)化線路設(shè)計(jì)，使用了本的ATmega16功能小板在范例中選用2.56V電壓基準(zhǔn)作Vref，差分通道10倍放大則單端電壓測(cè)量范圍02.56V,分辨率2.5mV差分+/-256mV分辨率0.5mV電流分辨率=50uA@10歐姆電流采樣電阻電流分辨率=500uA@1歐姆電流采樣電阻程序中需要把實(shí)測(cè)的基準(zhǔn)電壓代入常量Vref中，以獲得更準(zhǔn)確地結(jié)果我手中的樣片實(shí)測(cè)為2.556V@Vcc=5.0V本電路參考，沒(méi)有考 .代碼設(shè)計(jì)與說(shuō)明 *******策劃、整理與測(cè)試：(arm ****代碼設(shè)計(jì)： *******編譯器 ********************************/#include<avr/io.h>#include<avr/delay.h>#include<avr/signal.h>#include<avr/interrupt.h>/*宏INTERRUPT的用法與SIGNAL類似，區(qū)別 SIGNAL執(zhí)行時(shí)全局中斷觸發(fā)位被清除、其他中斷被INTERRUPT執(zhí)行時(shí)全局中斷觸發(fā)位被置位、其他中斷可嵌套執(zhí)另外avr-libc提供兩個(gè)API函數(shù)用于置位和清零全局中斷觸發(fā)位，它們是經(jīng)常用到的。分別是：voidsei(void)和voidcli(void)由interrupt.h定義*/#definein_Single0//PA0(ADC0)#definein_Diff_P3//PA3(ADC3)#definein_Diff_N2#defineAD_SE_ADC00x00//ADC0#defineAD_SE_ADC10x01//ADC1#defineAD_SE_ADC20x02//ADC2#defineAD_SE_ADC30x03//ADC3#defineAD_SE_ADC40x04#defineAD_SE_ADC50x05//ADC5#defineAD_SE_ADC60x06//ADC6#defineAD_SE_ADC70x07#defineAD_Diff0_0_10x0x08//ADC0+ADC0-,10#defineAD_Diff1_0_10x0x09//ADC1+ADC0-,10#defineAD_Diff0_0_200x0x0A//ADC0+ADC0-,200倍放大，校準(zhǔn)#defineAD_Diff1_0_200x0x0B//ADC1+ADC0-,200倍放#defineAD_Diff2_2_10x0x0C//ADC2+ADC2-,10#defineAD_Diff3_2_10x0x0D//ADC3+ADC2-,10#defineAD_Diff2_2_200x0x0E//ADC2+ADC2-,200倍放大，校準(zhǔn)#defineAD_Diff3_2_200x0x0F//ADC3+ADC2-,200倍放#defineAD_Diff0_1_1x0x10//ADC0+ADC1-#defineAD_Diff1_1_1x0x11//ADC1+ADC1-,校準(zhǔn)用#defineAD_Diff2_1_1x0x12//ADC2+ADC1-#defineAD_Diff3_1_1x0x13//ADC3+ADC1-#defineAD_Diff4_1_1x0x14//ADC4+ADC1-#defineAD_Diff5_1_1x0x15//ADC5+ADC1-#defineAD_Diff6_1_1x0x16//ADC6+ADC1-#defineAD_Diff7_1_1x0x17//ADC7+ADC1-//差分ADC2作負(fù)端，不放大#defineAD_Diff0_2_1x0x18//ADC0+ADC2-#defineAD_Diff1_2_1x0x19//ADC1+#defineAD_Diff2_2_1x0x1A//ADC2+ADC2-,校準(zhǔn)用#defineAD_Diff3_2_1x0x1B//ADC3+ADC2-#defineAD_Diff4_2_1x0x1C//ADC4+ADC2-#defineAD_Diff5_2_1x0x1D//ADC5+ADC2-#defineAD_SE_VBG0x1E//VBG能隙1.22V電壓基準(zhǔn),校準(zhǔn)#defineAD_SE_GND0x1F////1x10x8200x//在PDIP封裝下的差分輸入通道器件測(cè)試。只保證器件在TQFP與MLF封裝下正常工#defineVref2556//mVVref引腳電壓@5.0V//#defineVref2550//mV實(shí)測(cè)的Vref引腳電壓@3.3VunsignedintADC_SingleEnded;ADCintADC_Diff;ADCvolatileunsignedintADC_INT_SE;ADC/volatilevolatileunsignedcharADC_OK;//ADCvolatileunsignedintLED_Volt;//mVintLED_Curr;//100uA//仿真時(shí)在watch窗口，這些全局變量unsignedintread_adc(unsignedcharadc_input)//查詢方式ADC單端{(lán)//0xc0:選擇2.56V參考電ADCSRA|=(1<<ADSC);ADloop_until_bit_is_set(ADCSRA,ADIF);1AD束//while((ADCSRA&(1<<ADIF))==0);2好//loop_until_bit_is_clear(ADCSRA,ADSC);2C=0ADCSRA|=(1<<ADIF);1returnADC;}intread_adc_diff(unsignedcharadc_input)//查詢方式ADC差分通{unsignedintADMUX=(0xc0|adc_input);//adc_input：差分通道_delay_ms(1);>125uS2//可正可負(fù)+/-9bit-//Tiny26，ADC+ADC-,為if(ADC_FIX>=0x0200){ADC_FIX|=0xFC00;16}return}SIGNAL(SIG_ADC)//ADC{ADIFADC_INT_SE=ADC;//結(jié)果}int{longtemp32;ADC_SingleEnded=0;DDRx=0x00,PORTx=0x00PORTB=0xFF;//不用的管腳使 上拉電阻//作ADC輸入時(shí)，不可使能上拉電阻ADCSRA=(1<<ADEN)|0x06;ADC,64125KHz@8MHztemsei();while{Vref2556mV//查詢方式ADC0LED_Volt=(unsignedint)(temp32/1024);ADC_Diff=read_adc_diff(AD_Diff3_2_10x);ADC_Diff-=read_adc_diff(AD_Diff2_2_10x);//校準(zhǔn)OFFSET//查詢方式ADC3+,ADC2-10倍放大max+/-//101mA=10mVm