周六下午實驗二

D/A接口實1D/A2、掌握MAX504D/A轉換的使用方3D/ACPUD/A4D/A學習D/A接口原理，了解實現(xiàn)D/A系統(tǒng)對于系統(tǒng)的硬件要求。閱讀MAX504硬件：UP-NETARM2410-S實驗平臺、PC機Pentium500以上,硬盤10G以上：PC機操作系統(tǒng)REDHATLINUX ＋ARM-LINUX開發(fā)環(huán)境D/A轉換器的電路構成無太大差異一般按輸出是電流還是電壓能否作乘法運算等進行分類。大多數(shù)D/A轉換器由電阻陣列和n個電流開關（或電壓開關）構成。按數(shù)字輸輸出放大器部分的延遲，故常作為高速D/A轉換器使用。電流輸出型D/A轉換器很少直#include<stdio.h>#include<fcntl.h>#include<string.h>#include<sys/ioctl.h>#defineDA0_IOCTRL_WRITE0x10#defineDA1_IOCTRL_WRITE0x11#defineDA_IOCTRL_CLR0x12#defineMax504_FULL4.096fstaticintda_fd=-1;voidDelay(intt){}intmain(intargc,char**argv){floatv;unsignedintvalue;//char//unsignedintda_num=0;if(argc<3){printf("Errorparameter\n");printf("Inputas:\n");printf("da_id:selectbetween0and1\n");printf("num:range0.0~4.096\n");return}sscanf(argv[2],"%f",&v);if(v<0||v>Max504_FULL){printf("DAoutmustbetween:0to%f\n",Max504_FULL);return1;}value=(unsignedint)((v*1024.0f)/Max504_FULL);if((da_fd=open(DA_DEV,O_WRONLY))<0){printf("Erroropening/dev/exio/0rawdevice\n");return1;}if(strcmp(argv[1],"0")==ioctl(da_fd,DA_IOCTRL_CLR,0);//clearda.ioctl(da_fd,DA0_IOCTRL_WRITE,&value);}elseif(strcmp(argv[1],"1")==0){ioctl(da_fd,DA_IOCTRL_CLR,1);//clearda.ioctl(da_fd,DA1_IOCTRL_WRITE,&value);}#ifioctl(da_fd,DA_IOCTRL_CLR,0);//clearda.{ioctl(da_fd,DA0_IOCTRL_WRITE,&value);}printf("CurrentVoltageis%fv\n",v);return0;} da 1、D/A答：DA轉換器的電路構成無太大差異，一般按輸出時電流還是電壓、能否作乘法運算電壓輸出型（電流輸出型（乘算型（DAD/A（1）DAADDA簡歷DA則較長。其他指標還有線性度，轉換精度，溫度系數(shù)/MAX504（1）（2）（3）2.048V參考電使用方法：SCLKCPU時鐘接入的，CLR