/* Megumin LED display firmware
 * Copyright (C) 2018 Sebastian Götte <code@jaseg.net>
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "global.h"

int main(void) {
    //RCC->CR |= RCC_CR_HSEON;
    //while (!(RCC->CR&RCC_CR_HSERDY));
    RCC->CFGR &= ~RCC_CFGR_PLLMUL_Msk & ~RCC_CFGR_SW_Msk & ~RCC_CFGR_PPRE_Msk & ~RCC_CFGR_HPRE_Msk;
    RCC->CFGR |= ((12-2)<<RCC_CFGR_PLLMUL_Pos); /* PLL / 2 * 12 -> 48.0MHz */
    RCC->CR |= RCC_CR_PLLON;
    while (!(RCC->CR&RCC_CR_PLLRDY));
    RCC->CFGR |= (2<<RCC_CFGR_SW_Pos);
    SystemCoreClockUpdate();

    /* Turn on lots of neat things */
    RCC->AHBENR  |= RCC_AHBENR_GPIOAEN;

    GPIOA->MODER |=
          (1<<GPIO_MODER_MODER0_Pos)
        | (1<<GPIO_MODER_MODER1_Pos);

    int cnt = 0;
    int ph = 0;
    while (42) {
        if (cnt > 5000) {
            cnt = 0;
            ph += 1;
            ph %= 4;
        } else {
            cnt = cnt+1;
        }
        switch (ph) {
            case 0: GPIOA->ODR = 1; break;
            case 1: GPIOA->ODR = 3; break;
            case 2: GPIOA->ODR = 2; break;
            case 3: GPIOA->ODR = 0; break;
        }
    }
}

void NMI_Handler(void) {
    asm volatile ("bkpt");
}

void HardFault_Handler(void) __attribute__((naked));
void HardFault_Handler() {
    asm volatile ("bkpt");
}

void SVC_Handler(void) {
    asm volatile ("bkpt");
}


void PendSV_Handler(void) {
    asm volatile ("bkpt");
}