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Electronics => Beginners => Topic started by: neo on September 06, 2017, 03:30:09 am

Title: Arduino MAX7219 question
Post by: neo on September 06, 2017, 03:30:09 am

I will probably phrase this wrong, how do i use the arduino to read two 4 bit bcd codes and call the corresponding code for that, so for example 0000 0000 would call for

Code: [Select]

 output(0x01, 0x00); 

and 0000 0001 would be

Code: [Select]

 output(0x01, 0x01); 

the same digit except with 1 instead of 0.

The code i have running the max 7219 now though it doesn't do what i described as of yet.

Code: [Select]

#define MAX7219_DIN 7
#define MAX7219_CS  6
#define MAX7219_CLK 5

void initialise()
{
  digitalWrite(MAX7219_CS, HIGH);
  pinMode(MAX7219_DIN, OUTPUT);
  pinMode(MAX7219_CS, OUTPUT);
  pinMode(MAX7219_CLK, OUTPUT);
}

void output(byte address, byte data)
{
  digitalWrite(MAX7219_CS, LOW);
  shiftOut(MAX7219_DIN, MAX7219_CLK, MSBFIRST, address);
  shiftOut(MAX7219_DIN, MAX7219_CLK, MSBFIRST, data);
  digitalWrite(MAX7219_CS, HIGH);
}

void setup() {
  // put your setup code here, to run once:
  initialise();
  output(0x0f, 0x00); //display test register - test mode off
  output(0x0c, 0x01); //shutdown register - normal operation
  output(0x0b, 0x07); //scan limit register - display digits 0 thru 7
  output(0x0a, 0x0f); //intensity register - max brightness
  output(0x09, 0xff); //decode mode register - CodeB decode all digits
  output(0x08, 0x04); //digit 7 (leftmost digit) data
  output(0x07, 0x02);
  output(0x06, 0x00);
  output(0x05, 0x04);
  output(0x04, 0x02);
  output(0x03, 0x00);
  output(0x02, 0x04);
  output(0x01, 0x02); //digit 0 (rightmost digit) data


}

void loop() {
  // put your main code here, to run repeatedly:

}

EDIT: That is not my code, full credit for it goes to Julian Llett