Question

如何使用arduino上的analogRead中的值填充数组。每秒钟arduino从analog0读取值，我想把这些读数放到数组中。

Answer 1

假设您想要读取最多100个值，请执行以下操作：

<强> 1。技术不佳（使用阻止代码delay()）：

//let's say you want to read up to 100 values
const unsigned int numReadings = 100;
unsigned int analogVals[numReadings];
unsigned int i = 0;

void setup()
{
}

void loop()
{
  analogVals[i] = analogRead(A0);
  i++;
  if (i>=numReadings)
  {
    i=0; //reset to beginning of array, so you don't try to save readings outside of the bounds of the array
  }
  delay(1000); //wait 1 sec
}

如果这对您有用，请用绿色复选标记标记我的答案，说这是一个很好的答案。

注意：您不能使括号中的数字太大。例如：analogVals [2000]不起作用，因为它占用了太多RAM。

PS。这是Arduino在网站帮助中涵盖的非常基本的东西。从现在开始请参考此类问题，并先自己动手：http://arduino.cc/en/Reference/HomePage - ＆gt;点击“数据类型”下的“数组”。

<强> 2。替代方法（也是一种糟糕的技术，因为它使用阻塞代码delay()）：

//let's say you want to read up to 100 values
const unsigned int numReadings = 100;
unsigned int analogVals[numReadings];

void setup()
{
}

void loop()
{
  //take numReadings # of readings and store into array
  for (unsigned int i=0; i<numReadings; i++)
  {
    analogVals[i] = analogRead(A0);
    delay(1000); //wait 1 sec
  }
}

更新：2018年10月6日

第3。最好的技术（非阻塞方法 - 没有delay！）：

//let's say you want to read up to 100 values
const unsigned int numReadings = 100;
unsigned int analogVals[numReadings];
unsigned int i = 0;

void setup()
{
  Serial.begin(115200);
}

void loop()
{
  static uint32_t tStart = millis(); // ms; start time
  const uint32_t DESIRED_PERIOD = 1000; // ms
  uint32_t tNow = millis(); // ms; time now
  if (tNow - tStart >= DESIRED_PERIOD)
  {
    tStart += DESIRED_PERIOD; // update start time to ensure consistent and near-exact period

    Serial.println("taking sample");
    analogVals[i] = analogRead(A0);
    i++;
    if (i>=numReadings)
    {
      i = 0; //reset to beginning of array, so you don't try to save readings outside of the bounds of the array
    }
  }
}

<强> 4。专业类型方法（非阻塞方法，通过传递指针来避免全局变量，使用C stdint types，并使用静态变量来存储本地持久数据）：

// Function prototypes
// - specify default values here
bool takeAnalogReadings(uint16_t* p_numReadings = nullptr, uint16_t** p_analogVals = nullptr);

void setup()
{
  Serial.begin(115200);
  Serial.println("\nBegin\n");
}

void loop()
{
  // This is one way to just take readings
  // takeAnalogReadings();

  // This is a way to both take readings *and* read out the values when the buffer is full
  uint16_t numReadings;
  uint16_t* analogVals;
  bool readingsDone = takeAnalogReadings(&numReadings, &analogVals);
  if (readingsDone)
  {
    // Let's print them all out!
    Serial.print("numReadings = "); Serial.println(numReadings);
    Serial.print("analogVals = [");
    for (uint16_t i=0; i<numReadings; i++)
    {
      if (i!=0)
      {
        Serial.print(", ");
      }
       Serial.print(analogVals[i]);
    }
    Serial.println("]");
  }
}

// Function definitions:

//---------------------------------------------------------------------------------------------------------------------
// Take analog readings to fill up a buffer.
// Once the buffer is full, return true so that the caller can read out the data.
// Optionally pass in a pointer to get access to the internal buffer in order to read out the data from outside
// this function.
//---------------------------------------------------------------------------------------------------------------------
bool takeAnalogReadings(uint16_t* p_numReadings, uint16_t** p_analogVals)
{
  static const uint16_t NUM_READINGS = 10;
  static uint16_t i = 0; // index
  static uint16_t analogVals[NUM_READINGS];

  const uint32_t SAMPLE_PD = 1000; // ms; sample period (how often to take a new sample)
  static uint32_t tStart = millis(); // ms; start time
  bool bufferIsFull = false; // set to true each time NUM_READINGS have been taken

  // Only take a reading once per SAMPLE_PD
  uint32_t tNow = millis(); // ms; time now
  if (tNow - tStart >= SAMPLE_PD)
  {
    Serial.print("taking sample num "); Serial.println(i + 1);
    tStart += SAMPLE_PD; // reset start time to take next sample at exactly the correct pd
    analogVals[i] = analogRead(A0);
    i++;
    if (i >= NUM_READINGS)
    {
      bufferIsFull = true;
      i = 0; // reset to beginning of array, so you don't try to save readings outside of the bounds of the array
    }
  }

  // Assign the user-passed-in pointers so that the user can retrieve the data if they so desire to do it this way
  if (p_numReadings != nullptr)
  {
    *p_numReadings = NUM_READINGS;
  }
  if (p_analogVals != nullptr)
  {
    *p_analogVals = analogVals;
  }

  return bufferIsFull;
}

上一个代码的示例输出：

开始

取样品号1   取样2号   取样3号   取样4号   取样5号   取样数6
  取样7号   取样数8   取样数9   取样10号   numReadings = 10
  analogVals = [1023,1023,1023,1023,1023,687,0,0,0,0]
  取样1号   取样2号   取样3号   取样4号   取样5号   取样数6
  取样7号   取样数8   取样数9   取样10号   numReadings = 10
  analogVals = [0,0,0,0,0,0,0,0,0,0]

Arduino用arrayRead中的值填充数组

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