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基于瑞萨RZ/G2L处理器实现AD数模转换
文章目录
（1）DA转换
（2）[color=rgba(0, 0, 0, 0.7)]ADS1263简介
（3）电路设计
（4）参考例程
（1）DA转换
一个数字电路系统，当需要采集外界模拟量的使用需要进行AD转换，将模拟量转换成数字量，供单片机使用。单片机需要外部配置一个AD转换芯片来进行模拟量的采集，只需简单配置一下，便可以采集到AD转换后的数据。
AD转换（Analog to Digital）是模拟量转换数字量，那么DA转换（Digital to Analog）便是数字量转换成模拟量。
[color=rgba(0, 0, 0, 0.7)](2)ADS1263简介
（3）电路设计
见附件
（4）参考例程
#include <stdlib.h> //exit()
#include <signal.h> //signal()
#include <time.h>
#include "ADS1263.h"
#include "stdio.h"
#include <string.h>
// ADC1 test part
#define TEST_ADC1 1
// ADC1 rate test par
#define TEST_ADC1_RATE 0
// ADC2 test part
#define TEST_ADC2 0
// RTD test part
#define TEST_RTD 0
#define REF 5.08 //Modify according to actual voltage
//external AVDD and AVSS(Default), or internal 2.5V
void Handler(int signo)
{
//System Exit
printf("\r\n END \r\n");
DEV_Module_Exit();
exit(0);
}
int main(void)
{
UDOUBLE ADC[10];
UWORD i;
double RES, TEMP;
// Exception handling:ctrl + c
signal(SIGINT, Handler);
printf("ADS1263 Demo \r\n");
DEV_Module_Init();
// 0 is singleChannel, 1 is diffChannel
ADS1263_SetMode(0);
// The faster the rate, the worse the stability
// and the need to choose a suitable digital filter(REG_MODE1)
if(ADS1263_init_ADC1(ADS1263_400SPS) == 1) {
printf("\r\n END \r\n");
DEV_Module_Exit();
exit(0);
}
/* Test DAC */
// ADS1263_DAC(ADS1263_DAC_VLOT_3, Positive_A6, Open);
// ADS1263_DAC(ADS1263_DAC_VLOT_2, Negative_A7, Open);
if(TEST_ADC1) {
printf("TEST_ADC1\r\n");
#define ChannelNumber 5
UBYTE ChannelList[ChannelNumber] = {0, 1, 2, 3, 4}; // The channel must be less than 10
UDOUBLE Value[ChannelNumber] = {0};
while(1) {
ADS1263_GetAll(ChannelList, Value, ChannelNumber); // Get ADC1 value
for(i=0; i<ChannelNumber; i++) {
if((Value>>31) == 1)
printf("IN%d is -%lf \r\n", ChannelList, REF*2 - Value/2147483648.0 * REF); //7fffffff + 1
else
printf("IN%d is %lf \r\n", ChannelList, Value/2147483647.0 * REF); //7fffffff
}
for(i=0; i<ChannelNumber; i++) {
printf("\33[1A"); // Move the cursor up
}
}
}
else if(TEST_ADC2) {
printf("TEST_ADC2\r\n");
if(ADS1263_init_ADC2(ADS1263_ADC2_100SPS) == 1) {
printf("\r\n END \r\n");
DEV_Module_Exit();
exit(0);
}
while(1) {
ADS1263_GetAll_ADC2(ADC); // Get ADC2 value
for(i=0; i<10; i++) {
if((ADC>>23) == 1)
printf("IN%d is -%lf \r\n", i, REF*2 - ADC/8388608.0 * REF); //7fffff + 1
else
printf("IN%d is %lf \r\n", i, ADC/8388607.0 * REF); //7fffff
}
printf("\33[10A");//Move the cursor up
}
}
else if(TEST_ADC1_RATE) {
printf("TEST_ADC1_RATE\r\n");
struct timespec start={0, 0}, finish={0, 0};
clock_gettime(CLOCK_REALTIME, &start);
double time;
UBYTE isSingleChannel = 0;
if(isSingleChannel) {
for(i=0; i<10000; i++) {
ADS1263_GetChannalValue(0);
}
clock_gettime(CLOCK_REALTIME, &finish);
time = (double)(finish.tv_sec-start.tv_sec)*1000.0 + (double)(finish.tv_nsec-start.tv_nsec)/1000000.0;
printf("%lf ms\r\n", time);
printf("single channel %lf kHz\r\n", 10000 / time);
}
else {
for(i=0; i<10000; i++) {
ADS1263_GetChannalValue(0);
}
clock_gettime(CLOCK_REALTIME, &finish);
time = (double)(finish.tv_sec-start.tv_sec)*1000.0 + (double)(finish.tv_nsec-start.tv_nsec)/1000000.0;
printf("%lf ms\r\n", time);
printf("multi channel %lf kHz\r\n", 10000 / time);
}
}
else if(TEST_RTD) {
printf("TEST_RTD\r\n");
ADC[0] = ADS1263_RTD(ADS1263_DELAY_8d8ms, ADS1263_GAIN_1, ADS1263_20SPS);
RES = ADC[0]/2147483647.0 * 2.0 * 2000.0; //2000.0 -- 2000R, 2.0 -- 2*i
printf("Res is %lf \r\n", RES);
TEMP = (RES/100.0 - 1.0) / 0.00385; //0.00385 -- pt100
printf("Temp is %lf \r\n", TEMP);
printf("\33[2A");//Move the cursor up
}
return 0;
}
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