/**
  ******************************************************************************
  * @file    main.c
  * @author  MCU Application Team
  * @brief   Main program body
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2023 Puya Semiconductor Co.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by Puya under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2016 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "py32f090xx_ll_Start_Kit.h"

/* Private define ------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private user code ---------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
static void APP_SystemClockConfig(void);
static void APP_SystemClockDecrease(void);
static void APP_EnterLowPowerRun(void);
  
/**
  * @brief  Main program.
  * @param  None
  * @retval int
  */
int main(void)
{
  /* Enable SYSCFG and PWR clock */
  LL_APB1_GRP2_EnableClock(LL_APB1_GRP2_PERIPH_SYSCFG);
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_PWR);

  /* Initialize LED */
  BSP_LED_Init(LED_GREEN);

  /* Initialize BUTTON */
  BSP_PB_Init(BUTTON_KEY,BUTTON_MODE_GPIO);

  /* Turn on the LED */
  BSP_LED_On(LED_GREEN);
  
  /* Enter LpRun mode */
  APP_EnterLowPowerRun();
  
  /* LED off */
  BSP_LED_Off(LED_GREEN);
  
  /* Wait for the button to be pressed */
  while(BSP_PB_GetState(BUTTON_KEY) == 0);

  /* Set Voltage Regulator mode */
  LL_PWR_SetVoltageRegulatorMode(LL_PWR_VOLTAGE_REGULATOR_MODE_MR);

  /* Exit LpRun mode */
  LL_PWR_SetPowerMode(LL_PWR_MODE_RUN);
  
  /* Wait for both the flags MR_RDY and LPRUN_RUN_SWF to be set. */
  while((LL_PWR_IsActiveFlag_LPRUN_RUN_SWF() != 1) || LL_PWR_IsActiveFlag_MR_RDY() != 1)
  {}
  
  /* Configure system clock */
  APP_SystemClockConfig();
  
  while (1)
  {
    /* LED toggle */
    BSP_LED_Toggle(LED_GREEN);
    LL_mDelay(500);
  }
}

/**
  * @brief  Configure system clock
  * @param  None
  * @retval None
  */
static void APP_SystemClockConfig(void)
{
  /* Enable HSI */
  LL_RCC_HSI_Enable();
  while(LL_RCC_HSI_IsReady() != 1)
  {
  }

  /* Set AHB prescaler: HCLK = SYSCLK */
  LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1);

  /* Select HSISYS as system clock source */
  LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_HSISYS);
  while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_HSISYS)
  {
  }

  /* Set APB prescaler: PCLK = HCLK */
  LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_1);
  LL_Init1msTick(8000000);

  /* Update the SystemCoreClock global variable(which can be updated also through SystemCoreClockUpdate function) */
  LL_SetSystemCoreClock(8000000);
}

static void APP_SystemClockDecrease(void)
{
  /* Enable MSI */
  LL_RCC_MSI_Enable();
  LL_RCC_SetMSIDiv(LL_RCC_MSI_DIV_1);
  while(LL_RCC_MSI_IsReady() != 1)
  {
  }

  /* Set AHB prescaler: HCLK = SYSCLK */
  LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1);

  /* Select MSISYS as system clock source */
  LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_MSISYS);
  while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_MSISYS)
  {
  }
  
  /* Set APB prescaler: PCLK = HCLK */
  LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_1);
  LL_Init1msTick(2000000);

  /* Update the SystemCoreClock global variable(which can be updated also through SystemCoreClockUpdate function) */
  LL_SetSystemCoreClock(2000000);
}

/**
  * @brief  Enter low-power run mode
  * @param  None
  * @retval None
  */
static void APP_EnterLowPowerRun(void)
{
  /* Configure the System clock as MSISYS */
  APP_SystemClockDecrease();
  
  /* Enable PWR clock */
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_PWR);
  
  /* Set Low-Power mode */
  LL_PWR_SetPowerMode(LL_PWR_MODE_LOWPOWERRUN);
  
  /* Set Voltage Regulator mode */
  LL_PWR_SetVoltageRegulatorMode(LL_PWR_VOLTAGE_REGULATOR_MODE_LPR);
}

/**
  * @brief  Error executing function.
  * @param  None
  * @retval None
  */
void APP_ErrorHandler(void)
{
  while (1)
  {
  }
}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* Users can add their own printing information as needed,
     for example: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* Infinite loop */
  while (1)
  {
  }
}
#endif /* USE_FULL_ASSERT */

/************************ (C) COPYRIGHT Puya *****END OF FILE******************/
