Arduino内置教程-模拟-平稳模拟数据

简介

从模拟输入重复读取，计算运行平均值  并将其打印到计算机上。在数组中保留十个读数  不断平均他们，使值更平滑。

硬件要求

• Arduino or Genuino 开发板
• 10kΩ 电位计

电路

把电位计的一个引脚连接到5V，中间引脚连接到模拟引脚A0，最后的引脚连接到地。

原理图

样例代码

下面的代码顺序保存10个模拟引脚的读取值，一个接一个放进一个数组里。每一次有新的值，把所有值加起来，然后取平均值，把这个平均值用作平滑输出的数据。因为这种平均每次加一个新的值到数组里（好过一次等够10个新值），分析运行的均值之间并没有滞后时间。

改变数组的大小，通过改变 numReadings 为一个更大的值将会使保存数据变得比之前平滑。

// Define the number of samples to keep track of. The higher the number,

 // the more the readings will be smoothed, but the slower the output will

 // respond to the input. Using a constant rather than a normal variable lets

 // use this value to determine the size of the readings array.

 const int numReadings = 10;

int readings[numReadings]; // the readings from the analog input

 int readIndex = 0; // the index of the current reading

 int total = 0; // the running total

 int average = 0; // the average

int inputPin = A0;

void setup() {

 // initialize serial communication with computer:

 Serial.begin(9600);

 // initialize all the readings to 0:

 for (int thisReading = 0; thisReading < numReadings; thisReading++) {

 readings[thisReading] = 0;

 }

 }

void loop() {

 // subtract the last reading:

 total = total - readings[readIndex];

 // read from the sensor:

 readings[readIndex] = analogRead(inputPin);

 // add the reading to the total:

 total = total + readings[readIndex];

 // advance to the next position in the array:

 readIndex = readIndex + 1;

// if we're at the end of the array...

 if (readIndex >= numReadings) {

 // ...wrap around to the beginning:

 readIndex = 0;

 }

 // calculate the average:

 average = total / numReadings;

 // send it to the computer as ASCII digits

 Serial.println(average);

 delay(1); // delay in between reads for stability

 }