#include <stdio.h>
#include <math.h>
#include <stm32l432xx.h>
#include "ee14lib.h"

void delay_us(unsigned int us)
{
    // 4MHz clock, while loop is 4 cycles?
    volatile int i = us;
    while(i--){}
}


// This function is called by printf() to handle the text string
// We want it to be sent over the serial terminal, so we just delegate to that function
int _write(int file, char *data, int len) {
    serial_write(USART2, data, len);
    return len;
}

int main()
{
    uint32_t csr = RCC->CSR;  // Get the reset cause
    RCC->CSR |= RCC_CSR_RMVF; // Clear the reset cause flags

    host_serial_init(9600);

    // Set up the watchdog
    RCC->APB1ENR1 |= RCC_APB1ENR1_WWDGEN; // Enable power to the watchdog peripheral
    WWDG->CFR = (0b11 << WWDG_CFR_WDGTB_Pos) | 0x7F; // 8x prescaler, window at max val (off)
    WWDG->CR = WWDG_CR_WDGA | 0x7F; // Enable watchdog and set timer to 0x7F (max val)

    printf("Starting up...\n");

    while(1){
        printf("CSR: %08x\n", csr);
        delay_us(100000);
        WWDG->CR = 0x7F; // Feed the watchdog
    }

    return 0;
}