按下按钮时，键盘矩阵代码未返回正确的列号

Question

int ColumnPins = 4;  //How many column pins
int RowPins = 5; //How many row pins
int Columns[] = {0, 1, 2, 3}; //Column pinNumbers
int Rows[] = {4, 6, 7, 8, 9}; //Row pinNumbers

void setup() 
{
  pinMode(13, OUTPUT);
  for (int counter = 0; counter < ColumnPins; counter++) 
  { //set all the columns to output
    pinMode(Columns[counter], OUTPUT);
  }
  for (int counter = 0; counter < RowPins; counter++) 
   { //set all rows to input
    pinMode(Rows[counter],INPUT_PULLDOWN);
    }
}

void loop()
{
  for (int ColumnIndex = 0; ColumnIndex < ColumnPins; ColumnIndex++) //sets column pins to high 1 by 1 
  {
    digitalWrite(Columns[ColumnIndex], HIGH);
    RowScan(ColumnIndex); //calls function rowscan checks whether and row is HIGH 
    digitalWrite(Columns[ColumnIndex], LOW);
  }
}

void RowScan(int ColumnIndex) //Scans each rowpin and checks whether any reads high
{
  for (int RowIndex = 0; RowIndex < RowPins; RowIndex++) 
    {
      if (digitalRead(Rows[RowIndex]) == HIGH) //if Rows at rowindex is high
      {
        for (int blinks = 0; blinks <= RowIndex; blinks++)
        { //Outputs # of blinks based on which row HIGH was read
          // print index
          digitalWrite(13, HIGH); //LEDPIN high
          delay(250);
          digitalWrite(13, LOW);
          delay(500);
        }
        for (int blinks = 0; blinks <= ColumnIndex; blinks++)
        { //Outputs # of blinks based on which row HIGH was read
          // print index
          digitalWrite(13, HIGH); //LEDPIN high
          delay(100);
          digitalWrite(13, LOW);
          delay(100);
        }
      }
    else if (digitalRead(Rows[RowIndex]) == LOW) //Rows at index o is LOW
    {
      digitalWrite(13,LOW);
    }
  }
}

C++ Arduino IDE列根据按下的时间返回0-3之间的随机值，当某一行读为高时，它应该只返回设置为高的列。不确定如何修复，非常确定void loop()中的第一个for循环存在问题。

Answer 1

我认为最好是将索引打印到串行监视器上，看看它是否正常工作。试试下面这些代码。

int totalCols = 4;
int totalRows = 5;

// exclude pins 0 and 1 since these are used for Serial communication
int keyCols[] = { 2, 4, 5,  6     }; 
int keyRows[] = { 7, 8, 9, 10, 11 };

void setup() 
{
    Serial.begin(9600); // begin Serial Communication at 9600 baudrate
    pinMode(13, OUTPUT);
    for (int i = 0; i < totalCols; i++)
        pinMode(keyCols[i], OUTPUT);

    for (int i = 0; i < totalRows; i++) 
        pinMode(keyRows[i], INPUT); // you can use INPUT instead
}

void loop() {
    for (int i = 0; i < totalCols; i++) {
        digitalWrite(keyCols[i], HIGH);
        ScanActiveRows(i);
        digitalWrite(keyCols[i], LOW);
    }
}

void ScanActiveRows(int col) {
    delay(5); // wait for 5 milliseconds after setting column pin
    for (int row = 0; row < totalRows; row++) {
        if (digitalRead(keyRows[row]) == HIGH) {

            // print column and row indices
            Serial.print("Column : ");
            Serial.println(col);
            Serial.print("Row : ");
            Serial.println(row);

        }
        else if (digitalRead(keyRows[row]) == LOW) {
            digitalWrite(13,LOW);
        }
    }
}

如果上面的代码输出了准确的列和行，那么blink for循环就是问题所在。我希望这能帮到你。这是我第一次回答。:)