rush_pll_test.cpp

rush_pll_test.cpp

#include <cstdint>
#include <cstdio>

#define RUSH_REFERENCE_FREQ 50 // MHz
#define RUSH_INTERMEDIATE_FREQ 480 // MHz
#define RUSH_R_DIVIDER 1
#define RUSH_MOD 65536
#define RUSH_R_OUT_DIVIDER 1
#define FPFD (RUSH_REFERENCE_FREQ / RUSH_R_DIVIDER)

int main ()
{
    uint16_t freq = 3400;
    uint16_t rfout = freq - RUSH_INTERMEDIATE_FREQ;
    float N = (float) rfout / FPFD / RUSH_R_OUT_DIVIDER;
    uint16_t INT = N; // rounded to lower
    uint32_t FRAC = (N - INT) * RUSH_MOD;
    
    printf("rfout: %d\n", rfout);
    printf("FPFD: %d\n", FPFD);
    printf("N: %f\n", N);
    printf("INT: %d\n", INT);
    printf("FRAC: %d\n", FRAC);
    return 0;
}