# define TOTAL 252 // (<255 !!) int main(void) { uint8_t step=6, step2,reg1, reg2, n=0, up=1, cntr; srand(10); //Seed the rng reg1= rand() ; // The first random number while (1) { reg2= rand() ; // The second random number cntr= TOTAL; // Start with fresh counter while (1) { n+=(up)?1:-1; PORTB=(n>cntr)?reg2:reg1; up=(n==255)?0:((n==0)?1:up); if (cntr==0) break; if (n==0) cntr-= step; } reg1=reg2; step2=rand(); if((TOTAL % step2) ==0) step=step2; } }