Another MAX7219 example using random numbers to randomly light an LED in the matrix, you may want to increase the delay
Download and install the LedControl Arduino library as it is essential for using the MAX7219.
Code
#include “LedControl.h” // need the library LedControl lc=LedControl(12,11,10,1); // // pin 12 is connected to the MAX7219 pin 1 labelled DIN // pin 11 is connected to the CLK pin 13 labelled CLK // pin 10 is connected to LOAD pin 12 labelled as CS // 1 as we only have 1 MAX 7219 atatched long randNumberX; long randNumberY; void setup() { // the zero refers to the MAX7219 number lc.shutdown(0,false);// turn off power saving lc.setIntensity(0,4);// sets brightness (0~15 possible values) lc.clearDisplay(0);// clear screen Serial.begin(9600); // if analog input pin 0 is unconnected, random analog // noise will cause the call to randomSeed() to generate randomSeed(analogRead(0)); } void loop() { randNumberX = random(0,8); randNumberY = random(0,8); lc.setLed(0,randNumberX,randNumberY,true); // turns on LED at col, row delay(20); lc.setLed(0,randNumberX,randNumberY,false); // turns on LED at col, row delay(20); }
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