Arduino based RGB Matrix LED tester

RGB_Matrix_LED_tester.ino

#include <Adafruit_GFX.h>   // Core graphics library
#include <RGBmatrixPanel.h> // Hardware-specific library
#define CLK 8  // MUST be on PORTB!
#define LAT A3
#define OE  9
#define A   A0
#define B   A1
#define C   A2
 
// Last parameter = 'false' disable double-buffering
RGBmatrixPanel matrix(A, B, C, CLK, LAT, OE, false);
 
void setup() {
  matrix.begin();
}
 
void loop() {
  // fill the screen with red
  matrix.fillRect(0, 0, 32, 16, matrix.Color333(7, 0, 0));
  delay(1000);
 
  // fill the screen with green
  matrix.fillRect(0, 0, 32, 16, matrix.Color333(0, 7, 0));
  delay(1000);
 
  // fill the screen with blue
  matrix.fillRect(0, 0, 32, 16, matrix.Color333(0, 0, 7));
  delay(1000);
 
  // fill the screen with white
  matrix.fillRect(0, 0, 32, 16, matrix.Color333(7, 7, 7));
  delay(1000);
 
  // fill the screen with black
  matrix.fillScreen(matrix.Color333(0, 0, 0));
  delay(1000);
}