Arduino示例代码讲解：Row-Column Scanning an 8x8 LED matrix with X-Y input LED矩阵

Row-Column Scanning an 8x8 LED matrix with X-Y input LED矩阵

这段代码是一个Arduino示例程序，用于通过行-列扫描控制一个8x8的LED矩阵。它使用两个模拟输入（例如电位器）来控制光标的位置，并在LED矩阵上显示光标的位置。

/*
  Row-Column Scanning an 8x8 LED matrix with X-Y input

 This example controls an 8x8 LED matrix using two analog inputs

 created 27 May 2009
 modified 30 Aug 2011
 by Tom Igoe

 This example works for the Lumex  LDM-24488NI Matrix. See
 http://sigma.octopart.com/140413/datasheet/Lumex-LDM-24488NI.pdf
 for the pin connections

 For other LED cathode column matrixes, you should only need to change
 the pin numbers in the row[] and column[] arrays

 rows are the anodes
 cols are the cathodes
 ---------

 Pin numbers:
 Matrix:
 * Digital pins 2 through 13,
 * analog pins 2 through 5 used as digital 16 through 19
 Potentiometers:
 * center pins are attached to analog pins 0 and 1, respectively
 * side pins attached to +5V and ground, respectively.

 This example code is in the public domain.

 http://www.arduino.cc/en/Tutorial/RowColumnScanning

 see also http://www.tigoe.net/pcomp/code/category/arduinowiring/514 for more
 */


// 2-dimensional array of row pin numbers:
const int row[8] = {
   
  2, 7, 19, 5, 13, 18, 12, 16
};

// 2-dimensional array of column pin numbers:
const int col[8] = {
   
  6, 11, 10, 3, 17, 4, 8, 9
};

// 2-dimensional array of pixels:
int pixels[8][8];

// cursor position:
int x = 5;
int y = 5;

void setup() {
   
  // initialize the I/O pins as outputs
  // iterate over the pins:
  for (int thisPin = 0; thisPin < 8; thisPin++) {
   
    // initialize the output pins:
    pinMode(col[thisPin], OUTPUT);
    pinMode(row[thisPin], OUTPUT);
    // take the col pins (i.e. the cathodes) high to ensure that
    // the LEDS are off:
    digitalWrite(col[thisPin], HIGH);
  }

  // initialize the pixel matrix:
  f