ztimer frequency conversion module (64bit arithmetic) More...

Detailed Description

ztimer frequency conversion module (64bit arithmetic)

This ztimer module allows converting a lower-level ztimer clockwith a given frequency to another frequency.

It is configured by passing two parameters (div, mul). Given a lower clock frequency f_low and a desired upper frequency f_upper, div and mul must be chosen such that

(f_upper * mul / div) == f_lower

A div or mul value of 0 is treated as 1 (no multiplication or division by 0 is done).

On every ztimer_set(), the target offset is first multiplied by mul and then divided by div, before passing it to the lower ztimer's ztimer_set().

On every ztimer_now(), the value from the lower ztimer is first multiplied by div and then divided by mul.

Multiplication and division is done using 64bit multiplication / division, thus its use should be avoided in favour of more optimized conversion modules.


  1. if a ztimer_periph_timer with 250kHz is to be "sped up" to 1MHz, use div=4, mul=0
  2. if a ztimer with 1024Hz is to be converted to 1000Hz, use div=125, mul=128


file  convert_muldiv64.h
 ztimer frequency conversion module API

Data Structures

struct  ztimer_convert_muldiv64_t
 ztimer_convert_muldiv64 structure More...


void ztimer_convert_muldiv64_init (ztimer_convert_muldiv64_t *ztimer_convert_muldiv64, ztimer_clock_t *lower, unsigned div, unsigned mul)
 ztimer_convert_muldiv64 initialization function More...

Function Documentation

◆ ztimer_convert_muldiv64_init()

void ztimer_convert_muldiv64_init ( ztimer_convert_muldiv64_t ztimer_convert_muldiv64,
ztimer_clock_t lower,
unsigned  div,
unsigned  mul 

ztimer_convert_muldiv64 initialization function

[in]ztimer_convert_muldiv64instance to initialize
[in]lowerlower timer to convert
[in]divsee module doc
[in]mulsee module doc