Go Down

Topic: Help with PROGMEM use (Read 37 times) previous topic - next topic

xsolar36

Hoping someone can help with using this memory usage system as I need to have less RAM use.
I found that my program uses up the RAM budget on a 328 when specifying fonts for display.

code snippets
setup
const char font5x8[][5] PROGMEM = {
    {        0x00, 0x00, 0x00, 0x00, 0x00},         //         (Space)
.......};

use
 bit_data=pgm_read_byte((uint8_t*)font8x16[chr_addr][col]);         // Get character col

without the "PROGMEM" keyword and "pgm_read_byte" everything is fine. Add them in and the memory usage changes as expected, but I get gibberish.
Please help. Dave


PaulS

Quote
but I get gibberish
and that will continue to happen until you post ALL of your code.

The art of getting good answers lies in asking good questions.

Go Up