[syntax=c]TIM_TimeBaseStructure.TIM_Prescaler = 0;
TIM1->PSC = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
// TIM1->CR1 = TIM_CR1_DIR ustawiamy tylko gdy chcemy downcounter, zero jest domylne po resecie
TIM_TimeBaseStructure.TIM_Period = 4095;
TIM1->ARR = 4095;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
// Tu też zostają zera, w razie czego korzystamy z definicji bitów CDK[1:0] w rejestrze CR1 - TIM_CR1_CKD_0 i TIM_CR1_CKD_1
// np tak: TIM1->CR1 |= TIM_CR1_CKD_1; ustawi tDTS = 4*tCK_INT- patrz obrazek i reference manual
TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
// TIM1->RCR = 0; też można olac bo to wartosc domyslna.[/syntax]
Reszta jest w manualu procesora. Jeśli chcesz zmieniać tylko wartości output compare dla pozostałych kanałów to możesz użyć poprostu przypisania odpowiedniej wartości:
[syntax=c]TIM1->CCR1 = 2047;
TIM1->CCR2 = 1024;
TIM1->CCR3 = 511;[/syntax]
Do migania diodami na płytce discovery napisałem kiedyś taki kod:
main.c
[syntax=c]#include <stm32f4xx.h>
#include "soft_timer.h"
#define BITS 12
#define MAX 0xFFFFFFFF
#define SHIFT (32-BITS)
volatile uint32_t delay;
void SysTick_Handler(void);
void timer1_tick(void);
void timer2_tick(void);
void timer3_tick(void);
void timer4_tick(void);
void timer5_tick(void);
void timer6_tick(void);
void Tim4Init(void);
softtimer_t timer1, timer2, timer3, timer4, timer5, timer6;
uint32_t pwm[4];
uint8_t on_off[4], idx, dim, key_lock;
int main(void) {
register_timer(&timer1, 333, timer1_tick);
register_timer(&timer2, 700, timer2_tick);
register_timer(&timer3, 500, timer3_tick);
register_timer(&timer4, 1100, timer4_tick);
register_timer(&timer5, 5, timer5_tick);
register_timer(&timer6, 10, timer6_tick);
enable_timers();
RCC->AHB1ENR |= RCC_AHB1ENR_GPIOAEN; // zegar dla portu a
GPIOA->PUPDR = GPIO_PUPDR_PUPDR0_1; // pullup dla pinu A0
Tim4Init();
while(1) {
}
}
void SysTick_Handler(void) {
timer_event();
}
void timer1_tick(void) {
on_off[0] ^= 1;
}
void timer2_tick(void) {
on_off[1] ^= 1;
}
void timer3_tick(void) {
on_off[2] ^= 1;
}
void timer4_tick(void) {
on_off[3] ^= 1;
}
void timer5_tick(void) {
for(idx=0; idx<4; idx++) {
if (on_off[idx]) {
pwm[idx] += (MAX - pwm[idx]) / 12;// szybkoć rozpalania diody
}
else {
pwm[idx] -= pwm[idx] / 12;// szybkoć wygasania diody
}
}
if(!dim) {
TIM4->CCR1 = (MAX >> SHIFT) * on_off[0];
TIM4->CCR2 = (MAX >> SHIFT) * on_off[1];
TIM4->CCR3 = (MAX >> SHIFT) * on_off[2];
TIM4->CCR4 = (MAX >> SHIFT) * on_off[3];
}
else {
TIM4->CCR1 = pwm[0] >> SHIFT;
TIM4->CCR2 = pwm[1] >> SHIFT;
TIM4->CCR3 = pwm[2] >> SHIFT;
TIM4->CCR4 = pwm[3] >> SHIFT;
}
}
void timer6_tick(void) {
if((GPIOA->IDR & (1<<0)) && !key_lock) {
key_lock = 1;
dim ^= 1;
}
else if(!(GPIOA->IDR & (1<<0)) && key_lock) {
key_lock = 0;
}
}
void Tim4Init(void) {
RCC->APB1ENR |= RCC_APB1ENR_TIM4EN;//zegar dla tim4
RCC->AHB1ENR|=RCC_AHB1ENR_GPIODEN;
GPIOD->MODER |= (GPIO_MODER_MODER12_1) | (GPIO_MODER_MODER13_1) | (GPIO_MODER_MODER14_1) | (GPIO_MODER_MODER15_1);
GPIOD->AFR[1] = 0x22220000;// AF2 - funkcje alternatywne dla pinów 13 14 15 i 16 - patrz tabelka datasheet
//AFR[0] - piny 0 do 7 AFR[1] - piny 8 do 15
TIM4->PSC = 0;
TIM4->ARR = MAX >> SHIFT;// max wartosc pwm 16 bit
TIM4->CCMR1 |= TIM_CCMR1_OC1M_1 | TIM_CCMR1_OC1M_2 | TIM_CCMR1_OC1PE
| TIM_CCMR1_OC2M_1 | TIM_CCMR1_OC2M_2 | TIM_CCMR1_OC2PE;
TIM4->CCMR2 |= TIM_CCMR2_OC3M_1 | TIM_CCMR2_OC3M_2 | TIM_CCMR2_OC3PE
| TIM_CCMR2_OC4M_1 | TIM_CCMR2_OC4M_2 | TIM_CCMR2_OC4PE;
TIM4->CCER |= TIM_CCER_CC1E | TIM_CCER_CC2E | TIM_CCER_CC3E | TIM_CCER_CC4E; // compare output enable
TIM4->CR1 |= TIM_CR1_CEN; // counter enable
TIM4->EGR |= TIM_EGR_UG; //update generation
}[/syntax]
soft_timer.h
[syntax=c]/*
* soft_timer.h
*
* Created on: 19-07-2014
* Author: Federerer
*/
#ifndef SOFT_TIMER_H_
#define SOFT_TIMER_H_
#ifdef __cplusplus
extern "C" {
#endif
#define TIMERS_COUNT 5
typedef struct {
uint16_t interval;
uint16_t time;
void (*wsk)(void);
} softtimer_t;
extern uint8_t tick;
extern softtimer_t * wskazniki[];
extern uint8_t timer_n;
void enable_timers(void);
void register_timer ( softtimer_t * timer, uint16_t interval, void (*wsk)(void) );
void timer_event(void);
#ifdef __cplusplus
}
#endif
#endif /* SOFT_TIMER_H_ */[/syntax]
soft_timer.c
[syntax=c]#include <stm32f4xx.h>
#include <stdint.h>
#include "soft_timer.h"
softtimer_t *wskazniki[TIMERS_COUNT];
uint8_t timer_n;
void enable_timers(void) {
SysTick_Config(SystemCoreClock/1000);
}
void register_timer ( softtimer_t * timer, uint16_t interval, void (*wsk)(void) ) {
timer->interval = interval;
timer->time = interval;
timer->wsk = wsk;
wskazniki[timer_n] = timer;
timer_n++;
}
void timer_event(void) {
for(uint8_t i=0; i < timer_n; i++) {
wskazniki[i]->time--;
if(!(wskazniki[i]->time)) {
wskazniki[i]->time = wskazniki[i]->interval;
if(wskazniki[i]->wsk) wskazniki[i]->wsk();
}
}
}[/syntax]
Mam nadzieję, że coś się przyda
Statystyki: Napisane przez Federerer — 31 gru 2014, o 22:33
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