Re: Varvtalsräkning på digital ingång - Förslag?
Postat: 23 juli 2020, 13:48:00
Ja testa den. Smidigt med inbyggd funktion i stm32.
Jag har bara gjort så den är något mer användarvänlig.
Ni får gärna testa och säga vad ni tycker om den?
Kod: Markera allt
/*
* Use a timer and select combined channels -> Encoder Mode.
* Then select our prescaler and the counter period
* Then select Encoder Mode TI1 and TI2.
* Leave the rest as default
*/
void Encoder_init(Encoder *encoder, TIM_HandleTypeDef *htim, uint16_t one_rotation_pulses, uint32_t check_every_ms) {
encoder->htim = htim;
encoder->one_rotation_pulses = one_rotation_pulses;
encoder->check_every_ms = check_every_ms;
}
void count_encoder(Encoder *encoder) {
if (HAL_GetTick() - encoder->tick > encoder->check_every_ms) {
/* Control TIM for every check_every_ms */
encoder->cnt2 = encoder->htim->Instance->CNT;
/* Control the rotation count */
if (__HAL_TIM_IS_TIM_COUNTING_DOWN(encoder->htim)) {
encoder->dir = 1;
/* __HAL_TIM_IS_TIM_COUNTING_DOWN Exception when the macro is wrong configured */
if ((encoder->cnt2 > encoder->cnt1) && (encoder->cnt2 - encoder->cnt1 < 100))
encoder->dir = 0;
} else {
encoder->dir = 0;
/* __HAL_TIM_IS_TIM_COUNTING_DOWN Excepting when the macro gives error */
if ((encoder->cnt1 > encoder->cnt2) && (encoder->cnt1 - encoder->cnt2 < 100))
encoder->dir = 1;
}
if (encoder->dir) {
/* Down Counting */
if (encoder->cnt1 >= encoder->cnt2)
encoder->diff = encoder->cnt1 - encoder->cnt2;
else
encoder->diff = (encoder->htim->Instance->ARR + encoder->cnt1) - encoder->cnt2;
} else {
/* Up Counting */
if (encoder->cnt2 >= encoder->cnt1)
encoder->diff = encoder->cnt2 - encoder->cnt1;
else
encoder->diff = (encoder->htim->Instance->ARR + encoder->cnt2) - encoder->cnt1;
}
if ((encoder->htim->Instance->SMCR & 0x03) == 0x03) {
/* X4 Mode Countering increase with 4 Pulse */
encoder->speed = encoder->diff * 60 / 4 / encoder->one_rotation_pulses; //RPM x 60
} else {
/* X4 Mode Countering increase with 2 Pulse */
encoder->speed = encoder->diff * 60 / 2 / encoder->one_rotation_pulses; //RPM x 60
}
encoder->tick = HAL_GetTick();
encoder->cnt1 = encoder->htim->Instance->CNT;
}
}
float Encoder_getSpeed(Encoder *encoder){
return encoder->dir == 1 ? (float) encoder->speed : -((float) encoder->speed);
}
Kod: Markera allt
#ifndef SRC_ENCODER_ENCODER_H_
#define SRC_ENCODER_ENCODER_H_
#include "main.h"
typedef struct{
uint8_t dir;
uint16_t cnt1, cnt2, diff, speed, one_rotation_pulses;
uint32_t tick, check_every_ms;
TIM_HandleTypeDef* htim;
}Encoder;
void Encoder_init(Encoder* encoder, TIM_HandleTypeDef* htim, uint16_t one_rotation_pulses);
void count_encoder(Encoder *encoder);
float Encoder_getSpeed(Encoder *encoder);
#endif /* SRC_ENCODER_ENCODER_H_ */