How to declare a matrix that is stored in PROGMEM

Question

I am trying to write a header file that will drive a LED Matrix but I'm stuck with a syntax error which I cannot resolve

I've already added " ; " everywhere I thought it was necessary and checked https://www.nongnu.org/avr-libc/user-manual/pgmspace.html

#ifndef max7219_H_
#define max7219_H_

#include <io.h>
#include <pgmspace.h>
#include <delay.h>
#include <stdint.h>

#define SLAVE_SELECT PORTB &= ~( 1<<PB4 );     
#define SLAVE_DESELECT PORTB |= ~( 1<<PB4 ); 

char characters[96][5] PROGMEM = 
{ 
   {
    0b00000000,
    0b00000000,
    0b00000000,
    0b00000000,
    0b00000000 
    }  
};

ERROR IS : Error: max7219.h(15), #included from: p2.c: ';' expected

line 15 is char characters[96][5] PROGMEM = ...

Answer 1

const PROGMEM uint8_t characters[96][5] = {
    {
      0b00000000,
      0b00000000,
      0b00000000,
      0b00000000,
      0b00000000 
   },
    ... // 95 more symbols
 };

Note, if an array declared with dimension, it should contain all the data in the initializer, i.e. all 96 symbols.

UPD: The error could be caused by the code in pc2.c just before #include "max7219.h" If you have several "includes", then check the previous one. I.e:

#include "a.h"
#include "b.h"
#include "max7219.h"

the error may be at the end of b.h

Answer 2

You need to declare it const to put in flash. Also i am guessing that you need to make two arrays.

Try:

     const char c1[] PROGMEM = "1";
     const char c2[] PROGMEM = "2";

     const char * const strings[] PROGMEM = {c1, c2};