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Altera_Forum's avatar
Altera_Forum
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15 years ago

NIOS II C code tips?

hey everybody I'm trying to make a PWM using NIOSII and SOPC and i have reached the point where i need to wright the C code for my model but i can't find any documentation describing how to do it...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

In my opinion, pwm in software is a bad idea (especially if you work with FPGA) : because of interruptions, CPU instructions, access.....

For SOPC, you need a PIO.

For software, You need an counter (simple) or a timer (a little difficult) and some comparators. 


int i =0;
while(1)
{
  i++;
  if (i == periode)
  {
    IO_WRITE_...(0); // write '0' to your PIO
    i = 0;
  }
  elseif (i >= pwm)
  {
     IO_WRITE_...(1); // write '1' to your PIO
   }
//...
}