#include "stm32c0xx.h"  // Ensure this is the correct header file

void timer3_init(void) {
    // Enable clock for TIM3
    RCC->APBENR1 |= RCC_APBENR1_TIM3EN; // TIM3 is in APBENR1 for STM32C0

    // Configure TIM3
    TIM3->CR1 = 0;                // Disable TIM3
    TIM3->PSC = 15999;            // Prescaler (assuming 16 MHz clock)
    TIM3->ARR = 999;              // Auto-reload value for 1 ms delay
    TIM3->EGR = TIM_EGR_UG;       // Generate an update event
    TIM3->SR &= ~TIM_SR_UIF;      // Clear any previous update interrupt flag
    TIM3->CR1 |= TIM_CR1_CEN;     // Enable TIM3
}

void timer3_delay(uint32_t milliseconds) {
    for (uint32_t i = 0; i < milliseconds; i++) {
        while (!(TIM3->SR & TIM_SR_UIF)) {} // Wait for update interrupt flag
        TIM3->SR &= ~TIM_SR_UIF;           // Clear update interrupt flag
    }
    TIM3->CR1 &= ~TIM_CR1_CEN;            // Disable TIM3 after delay
}

int main(void) {
    // Enable clock for GPIOA
    RCC->IOPENR |= RCC_IOPENR_GPIOAEN;   // Enable GPIOA clock

    // Set PA5 as output
    GPIOA->MODER &= ~(3 << (5 * 2));  // Clear mode bits for PA5
    GPIOA->MODER |= (1 << (5 * 2));   // Set PA5 as output mode (01)

    while (1) {
        GPIOA->ODR ^= (1 << 5);   // Toggle PA5 (LED on/off)
        timer3_init();            // Initialize TIM3
        timer3_delay(500);        // 500 ms delay
        GPIOA->ODR ^= (1 << 5);  // Toggle PA5 (LED off)
        timer3_init();            // Reinitialize TIM3 for next delay
        timer3_delay(500);        // 500 ms delay
    }
}