You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
93 lines
2.7 KiB
93 lines
2.7 KiB
#define _CRT_SECURE_NO_DEPRECATE
|
|
#include <stdio.h>
|
|
#include <stdint.h>
|
|
#include <stdbool.h>
|
|
|
|
typedef struct
|
|
{
|
|
int autoreload;
|
|
int prescaler;
|
|
float realfreq;
|
|
} timer_config_t;
|
|
|
|
bool compute_timer_parameter(timer_config_t* config, int timer_in_clk /*mhz*/, int infreq /*hz*/)
|
|
{
|
|
float psc_x_arr =(float) timer_in_clk * 1000 /*定时器模块时钟*/ * 1000 / infreq;
|
|
uint32_t psc = 0;
|
|
uint32_t arr = 65534;
|
|
for (; arr > 2; arr--)
|
|
{
|
|
psc =(uint32_t)( psc_x_arr / arr);
|
|
if (psc >= 1)
|
|
{
|
|
uint32_t tmparr = psc_x_arr / psc;
|
|
if (tmparr >= 65534)
|
|
continue;
|
|
break;
|
|
}
|
|
}
|
|
if (psc == 0)
|
|
return false;
|
|
if (arr <= 3)
|
|
return false; //定时器一周期的分辨率太小了
|
|
arr = psc_x_arr / psc;
|
|
|
|
int psc_x_arr_real = arr * psc;
|
|
float realfreq = timer_in_clk * 1000.0 /*定时器模块时钟*/ * 1000 / psc_x_arr_real;
|
|
|
|
arr = arr - 1;
|
|
psc = psc - 1;
|
|
|
|
config->autoreload = arr;
|
|
config->prescaler = psc;
|
|
config->realfreq = realfreq;
|
|
// config->compare = arr / 2;
|
|
return false;
|
|
}
|
|
|
|
void dumpconfig_info(timer_config_t* config)
|
|
{
|
|
printf("* freq : %f \n", config->realfreq);
|
|
printf("* prescaler : %d \n", config->prescaler);
|
|
printf("* autoreload: %d \n", config->autoreload);
|
|
}
|
|
|
|
int main(int argc, char const* argv[])
|
|
{
|
|
if (argc != 3)
|
|
{
|
|
printf("%s timerInClk mhz expect_freq khz\n", argv[0]);
|
|
return -1;
|
|
}
|
|
|
|
float expect_freq = 0;
|
|
float timerInClk = 0;
|
|
|
|
sscanf(argv[1], "%f", &timerInClk);
|
|
sscanf(argv[2], "%f", &expect_freq);
|
|
|
|
printf("******************************************************\n");
|
|
printf("* author: zhaohe *\n");
|
|
printf("* e-mail: h_zhaohe@163.com *\n");
|
|
printf("******************************************************\n");
|
|
printf("*\n");
|
|
printf("* timerInClk : %f mhz\n", timerInClk);
|
|
printf("* expect freq: %f khz\n", expect_freq);
|
|
printf("*\n");
|
|
|
|
int32_t infreq = (int32_t)(expect_freq * 1000);
|
|
timer_config_t timerconfig_apb2;
|
|
|
|
compute_timer_parameter(&timerconfig_apb2, timerInClk, infreq);
|
|
|
|
printf("******************************************************\n");
|
|
printf("*\n");
|
|
printf("* timer_module_clk: %f mhz\n", timerInClk);
|
|
printf("* freq : %f khz\n", timerconfig_apb2.realfreq / 1000.0);
|
|
printf("* period : %f ms\n", (1.0 / timerconfig_apb2.realfreq * 1000));
|
|
printf("* prescaler : %d \n", timerconfig_apb2.prescaler);
|
|
printf("* autoreload : %d \n", timerconfig_apb2.autoreload);
|
|
printf("*\n");
|
|
|
|
return 0;
|
|
}
|