模数转换与模拟比较-avr ad范例

AVR模数(AD)转换范例程本范例使用 版本开本程序简单的示范了如何使用ATMEGA16的ADC模数转换器 查询方 数据格式的变换出于简化程序考虑，各种数据有对外输出，学习时建议使用JTAGICE硬件仿真电路图设计为简化线路设计，使用了本的ATmega16功能小板在范例中选用2.56V电压基准作Vref，差分通道10倍放大则单端电压测量范围02.56V,分辨率2.5mV差分+/-256mV分辨率0.5mV电流分辨率=50uA@10欧姆电流采样电阻电流分辨率=500uA@1欧姆电流采样电阻程序中需要把实测的基准电压代入常量Vref中，以获得更准确地结果我手中的样片实测为2.556V@Vcc=5.0V本电路参考，没有考 .代码设计与说明 *******策划、整理与测试：(arm ****代码设计： *******编译器 ********************************/#include<avr/io.h>#include<avr/delay.h>#include<avr/signal.h>#include<avr/interrupt.h>/*宏INTERRUPT的用法与SIGNAL类似，区别 SIGNAL执行时全局中断触发位被清除、其他中断被INTERRUPT执行时全局中断触发位被置位、其他中断可嵌套执另外avr-libc提供两个API函数用于置位和清零全局中断触发位，它们是经常用到的。分别是：voidsei(void)和voidcli(void)由interrupt.h定义*/#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，校准#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，校准#defineAD_Diff3_2_200x0x0F//ADC3+ADC2-,200倍放#defineAD_Diff0_1_1x0x10//ADC0+ADC1-#defineAD_Diff1_1_1x0x11//ADC1+ADC1-,校准用#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作负端，不放大#defineAD_Diff0_2_1x0x18//ADC0+ADC2-#defineAD_Diff1_2_1x0x19//ADC1+#defineAD_Diff2_2_1x0x1A//ADC2+ADC2-,校准用#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电压基准,校准#defineAD_SE_GND0x1F////1x10x8200x//在PDIP封装下的差分输入通道器件测试。只保证器件在TQFP与MLF封装下正常工#defineVref2556//mVVref引脚电压@5.0V//#defineVref2550//mV实测的Vref引脚电压@3.3VunsignedintADC_SingleEnded;ADCintADC_Diff;ADCvolatileunsignedintADC_INT_SE;ADC/volatilevolatileunsignedcharADC_OK;//ADCvolatileunsignedintLED_Volt;//mVintLED_Curr;//100uA//仿真时在watch窗口，这些全局变量unsignedintread_adc(unsignedcharadc_input)//查询方式ADC单端{//0xc0:选择2.56V参考电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)//查询方式ADC差分通{unsignedintADMUX=(0xc0|adc_input);//adc_input：差分通道_delay_ms(1);>125uS2//可正可负+/-9bit-//Tiny26，ADC+ADC-,为if(ADC_FIX>=0x0200){ADC_FIX|=0xFC00;16}return}SIGNAL(SIG_ADC)//ADC{ADIFADC_INT_SE=ADC;//结果}int{longtemp32;ADC_SingleEnded=0;DDRx=0x00,PORTx=0x00PORTB=0xFF;//不用的管脚使 上拉电阻//作ADC输入时，不可使能上拉电阻ADCSRA=(1<<ADEN)|0x06;ADC,64125KHz@8MHztemsei();while{Vref2556mV//查询方式ADC0LED_Volt=(unsignedint)(temp32/1024);ADC_Diff=read_adc_diff(AD_Diff3_2_10x);ADC_Diff-=read_adc_diff(AD_Diff2_2_10x);//校准OFFSET//查询方式ADC3+,ADC2-10倍放大max+/-//101mA=10mVm