DDS Signal from array (not from PROGMEM)

Hey there,
I am working on a signal generator by using this tutorial:

The Signal gets generated by an array that is stored in PROGMEM.:

const PROGMEM int sine256[]  = {
  127,130,133,136,139,143,146,149,152,155,158,161,164,167,170,173,176,178,181,184,187,190,192,195,198,200,203,205,208,210,212,215,217,219,221,223,225,227,229,231,233,234,236,238,239,240,
  242,243,244,245,247,248,249,249,250,251,252,252,253,253,253,254,254,254,254,254,254,254,253,253,253,252,252,251,250,249,249,248,247,245,244,243,242,240,239,238,236,234,233,231,229,227,225,223,
  221,219,217,215,212,210,208,205,203,200,198,195,192,190,187,184,181,178,176,173,170,167,164,161,158,155,152,149,146,143,139,136,133,130,127,124,121,118,115,111,108,105,102,99,96,93,90,87,84,81,78,
  76,73,70,67,64,62,59,56,54,51,49,46,44,42,39,37,35,33,31,29,27,25,23,21,20,18,16,15,14,12,11,10,9,7,6,5,5,4,3,2,2,1,1,1,0,0,0,0,0,0,0,1,1,1,2,2,3,4,5,5,6,7,9,10,11,12,14,15,16,18,20,21,23,25,27,29,31,
  33,35,37,39,42,44,46,49,51,54,56,59,62,64,67,70,73,76,78,81,84,87,90,93,96,99,102,105,108,111,115,118,121,124
};

volatile unsigned long phaccu1;   // pahse accumulator
volatile unsigned long tword_m1;  // dds tuning word m

int frequency=440; //Set Frequency
const double refclk=31376.6; //Reference Clock

tword_m1=pow(2,32)*frequency/refclk;  // calulate DDS new tuning word
phaccu1=phaccu1+tword_m1; // soft DDS, phase accu with 32 bits
icnt1=phaccu1 >> 24;     // use upper 8 bits for phase accu as frequency information
OCR1A=pgm_read_byte_near(sine256 + icnt1);

When the array is stored in PROGMEM the sine output is working fine but when I want to use an array that is editable because its not in PROGMEM (deleted "const PROGMEM") then i just get a crunchy noise:

int sine256[]  = {
  127,130,133,136,139,143,146,149,152,155,158,161,164,167,170,173,176,178,181,184,187,190,192,195,198,200,203,205,208,210,212,215,217,219,221,223,225,227,229,231,233,234,236,238,239,240,
  242,243,244,245,247,248,249,249,250,251,252,252,253,253,253,254,254,254,254,254,254,254,253,253,253,252,252,251,250,249,249,248,247,245,244,243,242,240,239,238,236,234,233,231,229,227,225,223,
  221,219,217,215,212,210,208,205,203,200,198,195,192,190,187,184,181,178,176,173,170,167,164,161,158,155,152,149,146,143,139,136,133,130,127,124,121,118,115,111,108,105,102,99,96,93,90,87,84,81,78,
  76,73,70,67,64,62,59,56,54,51,49,46,44,42,39,37,35,33,31,29,27,25,23,21,20,18,16,15,14,12,11,10,9,7,6,5,5,4,3,2,2,1,1,1,0,0,0,0,0,0,0,1,1,1,2,2,3,4,5,5,6,7,9,10,11,12,14,15,16,18,20,21,23,25,27,29,31,
  33,35,37,39,42,44,46,49,51,54,56,59,62,64,67,70,73,76,78,81,84,87,90,93,96,99,102,105,108,111,115,118,121,124
};

volatile unsigned long phaccu1;   // pahse accumulator
volatile unsigned long tword_m1;  // dds tuning word m

int frequency=440; //Set Frequency
const double refclk=31376.6; //Reference Clock

tword_m1=pow(2,32)*frequency/refclk;  // calulate DDS new tuning word
phaccu1=phaccu1+tword_m1; // soft DDS, phase accu with 32 bits
icnt1=phaccu1 >> 24;     // use upper 8 bits for phase accu as frequency information
OCR1A=pgm_read_byte_near(sine256 + icnt1);

I have tested a bit around by deleting phm_read_byte_near because it's not an pgm vaiable anymore but these doesn't seem to work also.
I searched the internet around to see how I must change the Array to get it like an array that is stored in PRGMEM but I doesn't fine something... :confused:

I got the answer from the guy who has made the tutorial. Very friendly dude he guided me direct to the problem:

OCR1A=pgm_read_byte_near(sine256 + icnt1);

The command above is inside the timer function itself so i must set the array to a specific point (not inserting the whole array itself):

OCR1A=sine256[icnt1];

Anyways thanks :slight_smile: