PWM generation error

[027iconic]

I tried generating PWM on my stm32g070rb but when I connected my PA7 and GND to my oscilloscope, the output I got does not look like a pwm signal in any way, I have verified my connections and now I think the error is from my code.

[waclawek.jan]

I don't see anything wrong with that code.

Plain blinky (i.e. setting PA7 as GPIO Output, and then toggling it in a loop using a loop-delay) works?

JW

PS. You can post code using the </> icon at the top of editor.

[AScha.3]

You should learn about, how to use/set a scope first.

-> set probes to 10:1 and adjust them.

[MM..1]

Next bare metal musician. You know what RISC exactly mean?

And debuger peripheral view ? And your code for better reading

void GPIOA_Init(void) {
    // Enable the clock for GPIOA
    RCC->IOPENR |= RCC_IOPENR_GPIOAEN;
    // Set PA7 to alternate function mode (AF1 for TIM3_CH2)
    GPIOA->MODER &= ~GPIO_MODER_MODE7_Msk;
    GPIOA->MODER |= GPIO_MODER_MODE7_1; // Alternate function mode
    // Set the alternate function to AF1 (TIM3_CH2)
    GPIOA->AFR[0] &= ~GPIO_AFRL_AFSEL7_Msk;
    GPIOA->AFR[0] |= (1 << GPIO_AFRL_AFSEL7_Pos); // AF1
}
void TIM3_Init(void) {
    // Enable the clock for Timer 3
    RCC->APBENR1 |= RCC_APBENR1_TIM3EN;
    // Reset and configure Timer 3
    TIM3->CR1 = 0; // Reset the control register
    TIM3->PSC = 15999; // Prescaler value (assuming a 16 MHz clock, this gives a 1 kHz timer clock)
    TIM3->ARR = 250; // Auto-reload value (for 1 kHz PWM frequency)
    // Set PWM mode 1 on channel 2 and enable preload
    TIM3->CCMR1 &= ~TIM_CCMR1_OC2M_Msk;
    TIM3->CCMR1 |= (6 << TIM_CCMR1_OC2M_Pos); // PWM mode 1
    TIM3->CCMR1 |= TIM_CCMR1_OC2PE; // Enable preload
    // Set the compare value (duty cycle, here 50%)
    TIM3->CCR2 = 125;
    // Enable capture/compare on channel 2
    TIM3->CCER |= TIM_CCER_CC2E;
    // Enable auto-reload preload
    TIM3->CR1 |= TIM_CR1_ARPE;
    // Enable the counter
    TIM3->CR1 |= TIM_CR1_CEN;
    // Generate an update event to reload the prescaler value immediately
    TIM3->EGR = TIM_EGR_UG;
}


int main(void) {
    SystemClock_Config(); // Configure the system clock
    GPIOA_Init(); // Initialize GPIOA
    TIM3_Init(); // Initialize Timer 3

    while (1) {
        // Main loop does nothing, PWM signal is generated by the timer
    }
}

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