/********************************** (C) COPYRIGHT *******************************
 * File Name          : main.c
 * Author             : WCH
 * Version            : V1.0.0
 * Date               : 2021/06/06
 * Description        : Main program body.
 *********************************************************************************
 * Copyright (c) 2021 Nanjing Qinheng Microelectronics Co., Ltd.
 * Attention: This software (modified or not) and binary are used for 
 * microcontroller manufactured by Nanjing Qinheng Microelectronics.
 *******************************************************************************/

/*
 *@Note
 *low power, stop mode routine:
 *EXTI_Line0(PA0)
 *This routine demonstrates WFI enters sleep mode, PA0 pin input low level triggers
 *external interrupt EXTI_Line0 exits stop mode,Program execution continues after wake-up.
 *
 */

#include "debug.h"

/* Global define */

/* Global Variable */

/*********************************************************************
 * @fn      EXTI0_INT_INIT
 *
 * @brief  Initializes EXTI0 collection.
 *
 * @return  none
 */
void EXTI0_INT_INIT(void)
{
    GPIO_InitTypeDef GPIO_InitStructure = {0};
    EXTI_InitTypeDef EXTI_InitStructure = {0};
    NVIC_InitTypeDef NVIC_InitStructure = {0};

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO | RCC_APB2Periph_GPIOA, ENABLE);

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);

    /* GPIOA.0 ----> EXTI_Line0 */
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource0);
    EXTI_InitStructure.EXTI_Line = EXTI_Line0;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_Init(&EXTI_InitStructure);

    NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

/*********************************************************************
 * @fn      main
 *
 * @brief   Main program.
 *
 * @return  none
 */
int main(void)
{
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    SystemCoreClockUpdate();
    Delay_Init();
    USART_Printf_Init(115200);
    printf("SystemClk:%d\r\n", SystemCoreClock);
    printf( "ChipID:%08x\r\n", DBGMCU_GetCHIPID() );
    printf("Stop Mode Test\r\n");
    EXTI0_INT_INIT();

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE);
    printf("\r\n ********** \r\n");
    PWR_EnterSTOPMode(PWR_Regulator_LowPower, PWR_STOPEntry_WFI);
    printf("\r\n ########## \r\n");

    while(1)
    {
        Delay_Ms(1000);
        printf("Run in main\r\n");
    }
}