parafraktor-stm32/Src/stepper.c

#include "stm32g0b1xx.h"
#include "stepper.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

#include "SEGGER_SYSVIEW.h"
#include "uart_dmx.h"

stepper_T steppers[] = {
    {.en_port=GPIOC, .en_pin=11, .dir_port=GPIOB, .dir_pin=4, .step_port=GPIOE, .step_pin=2, .home_port=GPIOF, .home_pin=3}
};

void set_pins(stepper_T* stp){
    // Set direction (00: Input, 01: Output, 10: Alternate function, 11: Analog)

    // enable
    stp->en_port->MODER &= ~(0x3 << (stp->en_pin * 2));
    stp->en_port->MODER |=  (0x1 << (stp->en_pin * 2));

    // direction
    stp->dir_port->MODER &= ~(0x3 << (stp->dir_pin * 2));
    stp->dir_port->MODER |=  (0x1 << (stp->dir_pin * 2));

    // step
    stp->step_port->MODER &= ~(0x3 << (stp->step_pin * 2));
    stp->step_port->MODER |=  (0x1 << (stp->step_pin * 2));

    // home switch
    stp->home_port->MODER &= ~(0x3 << (stp->home_pin * 2));

    // make shure stepper is enabled (active low)
    stp->en_port->BSRR |= (0x1 << (stp->en_pin + 16));
}

void stepper_gpio_init(){
    RCC->IOPENR |= RCC_IOPENR_GPIOBEN;
    RCC->IOPENR |= RCC_IOPENR_GPIOCEN;
    RCC->IOPENR |= RCC_IOPENR_GPIOEEN;
    RCC->IOPENR |= RCC_IOPENR_GPIOFEN;

    for(uint8_t i=0; i<(sizeof(steppers)/sizeof(stepper_T)); i++){
        set_pins(&steppers[i]);
    }
}

void Timer1_Init(void) {
    // Step 1: Enable the clock for Timer 1
    RCC->APBENR2 |= RCC_APBENR2_TIM1EN;  // Enable TIM1 clock

    // Step 2: Configure Timer 1
    TIM1->PSC = 64;
    TIM1->ARR = 100;
    TIM1->DIER |= TIM_DIER_UIE; // Enable update interrupt

    // Step 3: Enable Timer 1
    TIM1->CR1 |= TIM_CR1_CEN; // Enable the timer

    // Step 4: Enable the interrupt in NVIC
    NVIC_EnableIRQ(TIM1_BRK_UP_TRG_COM_IRQn); // Enable Timer 1 interrupt in NVIC
}

// Timer 1 Update Interrupt Handler
void TIM1_BRK_UP_TRG_COM_IRQHandler(void) {
    SEGGER_SYSVIEW_RecordEnterISR();
    if (TIM1->SR & TIM_SR_UIF) { // Check if the update interrupt flag is set
        TIM1->SR &= ~TIM_SR_UIF; // Clear the update interrupt flag

        //SEGGER_SYSVIEW_PrintfHost("do step");
        do_steps();
    }
    SEGGER_SYSVIEW_RecordExitISR();
}

void do_steps(){
    static uint32_t timer = 0;
    timer++;

    for(uint8_t i=0; i<(sizeof(steppers)/sizeof(stepper_T)); i++){
        if(steppers[i].ramp_to_speed != 0 && steppers[i].next_step == timer){
            /* ramp speed */
            if(steppers[i].speed < steppers[i].ramp_to_speed)
               steppers[i].speed++;
            if(steppers[i].speed > steppers[i].ramp_to_speed)
               steppers[i].speed--;

            /* limit max speed */
            if(steppers[i].speed >= 100)
               steppers[i].speed=100;
            if(steppers[i].speed <= -100)
               steppers[i].speed=-100;

            /* get direction from sign */
            if(steppers[i].speed>0)
                steppers[i].dir_port->BSRR |= 1 << steppers[i].dir_pin;
            if(steppers[i].speed<0)
                steppers[i].dir_port->BSRR |= 1 << (steppers[i].dir_pin + 16);

            /* calculate next step time */
            steppers[i].next_step = timer + (1000/abs(steppers[i].speed)); // should be safe for 1 overflow

            /* step and count position */
            steppers[i].step_port->ODR ^= 1 << steppers[i].step_pin;
            if(steppers[i].speed>0)
                steppers[i].pos++;
            if(steppers[i].speed<0)
                steppers[i].pos--;
                
            printf("pos %d\tspeed %d\n", steppers[i].pos, steppers[i].speed);
        }

        if(steppers[i].homed){
            int16_t old_ramp_to_speed = steppers[i].ramp_to_speed;

            steppers[i].ramp_to_speed = rxBuffer[1] - steppers[i].pos;

            if(steppers[i].ramp_to_speed != 0 && old_ramp_to_speed == 0)
                steppers[i].next_step = timer+1;
        }
        else{
            if(~(steppers[i].home_port->IDR) & (1 << steppers[i].home_pin)){
                steppers[i].pos = 0;
                steppers[i].homed = 1;
                steppers[i].speed = 0;
                steppers[i].ramp_to_speed = 0;
                printf("homed %d\n", i);
            }
            else{
                if(steppers[i].ramp_to_speed == 0){
                    steppers[i].ramp_to_speed=10;
                    steppers[i].next_step = timer+1;
                }
            }
        }
    }
}