#define CLOCK_FREQUENCY 168000ULL

unsigned int ms_to_ticks(unsigned int ms) {
    return ms * (CLOCK_FREQUENCY/3);
}

void delay_routine(unsigned int delay_counter) {
    asm("mov r1, %[input]\n"
    "delay_loop:\n"
    "subs r1, #1\n"
    "bne delay_loop\n"
    : [input] "=r" (delay_counter));
}

void delay_ms(unsigned int seconds) {
    delay_routine(ms_to_ticks(seconds));
}