8X8 matrix display

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jnunes
 
Posts: 6
Joined: Tue May 03, 2016 1:03 pm

8X8 matrix display

Post by jnunes »

Hi

I am trying to get numbers to display on the 8x8 matrix. When the program starts, it does display 1 , but it then is blank after that. Please look at my code. Thank you

Code: Select all

/*************************************************** 
  This is a library for our I2C LED Backpacks

  Designed specifically to work with the Adafruit LED Matrix backpacks 
  ----> http://www.adafruit.com/products/872
  ----> http://www.adafruit.com/products/871
  ----> http://www.adafruit.com/products/870

  These displays use I2C to communicate, 2 pins are required to 
  interface. There are multiple selectable I2C addresses. For backpacks
  with 2 Address Select pins: 0x70, 0x71, 0x72 or 0x73. For backpacks
  with 3 Address Select pins: 0x70 thru 0x77

  Adafruit invests time and resources providing this open source code, 
  please support Adafruit and open-source hardware by purchasing 
  products from Adafruit!

  Written by Limor Fried/Ladyada for Adafruit Industries.  
  BSD license, all text above must be included in any redistribution
 ****************************************************/

#include <Wire.h>
#include <Adafruit_GFX.h>
#include "Adafruit_LEDBackpack.h"

Adafruit_8x8matrix matrix = Adafruit_8x8matrix();

void setup() {
  Serial.begin(9600);
  Serial.println("8x8 LED Matrix Test");
  int i=0;
  matrix.begin(0x70);// pass in the address

}



void loop() {
  
  matrix.clear();
  matrix.print('1');
  matrix.writeDisplay();
  delay(500);
  
  matrix.clear();
  matrix.print('2');
  matrix.writeDisplay();
  delay(500); 

  matrix.clear();
  matrix.print('3');
  matrix.writeDisplay();
  delay(500);

  matrix.clear();
  matrix.print('4');
  matrix.writeDisplay();
  delay(500);

} 
Last edited by Franklin97355 on Sun May 09, 2021 7:49 pm, edited 1 time in total.
Reason: Added code tags

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Franklin97355
 
Posts: 23910
Joined: Mon Apr 21, 2008 2:33 pm

Re: 8X8 matrix display

Post by Franklin97355 »

Which matrix did you get and how do you have it connected?

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jnunes
 
Posts: 6
Joined: Tue May 03, 2016 1:03 pm

Re: 8X8 matrix display

Post by jnunes »

I have this one
https://www.adafruit.com/product/870

I have it wired to an Arduino Uno board and I am using the SCL and SDA connectors on the Arduino Uno board. The example code works perfect. But I can not get it ti display numbers. This is for a score board project

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