/* mbed Microcontroller Library
* Copyright (c) 2006-2017 ARM Limited
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* This file configures the system clock as follows:
*-------------------------------------------------------------------------------------------
* System clock source | 1- PLL_HSE_EXTC / DEVICE_USBDEVICE | 3- PLL_HSI / DEVICE_USBDEVICE
* | (external 8 MHz clock) | (internal 8 MHz)
* | 2- PLL_HSE_XTAL / DEVICE_USBDEVICE |
* | (external 8 MHz xtal) |
*-------------------------------------------------------------------------------------------
* SYSCLK(MHz) | 72 / 72 | 64 / 48
*-------------------------------------------------------------------------------------------
* AHBCLK (MHz) | 72 / 72 | 64 / 48
*-------------------------------------------------------------------------------------------
* APB1CLK (MHz) | 36 / 36 | 32 / 24
*-------------------------------------------------------------------------------------------
* APB2CLK (MHz) | 72 / 72 | 64 / 48
*-------------------------------------------------------------------------------------------
*/
#include "stm32f1xx.h"
#include "mbed_error.h"
#define USE_PLL_HSE_EXTC 0x8 // Use external clock (ST Link MCO)
#define USE_PLL_HSE_XTAL 0x4 // Use external xtal (X3 on board - not provided by default)
#define USE_PLL_HSI 0x2 // Use HSI internal clock
#if ( ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL) || ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC) )
uint8_t SetSysClock_PLL_HSE(uint8_t bypass);
#endif /* ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL) || ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC) */
#if ((CLOCK_SOURCE) & USE_PLL_HSI)
uint8_t SetSysClock_PLL_HSI(void);
#endif /* ((CLOCK_SOURCE) & USE_PLL_HSI) */
/**
* @brief Configures the System clock source, PLL Multiplier and Divider factors,
* AHB/APBx prescalers and Flash settings
* @note This function should be called only once the RCC clock configuration
* is reset to the default reset state (done in SystemInit() function).
* @param None
* @retval None
*/
void SetSysClock(void)
{
#if ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC)
/* 1- Try to start with HSE and external clock */
if (SetSysClock_PLL_HSE(1) == 0)
#endif
{
#if ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL)
/* 2- If fail try to start with HSE and external xtal */
if (SetSysClock_PLL_HSE(0) == 0)
#endif
{
#if ((CLOCK_SOURCE) & USE_PLL_HSI)
/* 3- If fail start with HSI clock */
if (SetSysClock_PLL_HSI() == 0)
#endif
{
{
error("SetSysClock failed\n");
}
}
}
}
/* Output clock on MCO1 pin(PA8) for debugging purpose */
//HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_SYSCLK, RCC_MCODIV_1); // 72 MHz or 64 MHz
}
#if ( ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL) || ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC) )
/******************************************************************************/
/* PLL (clocked by HSE) used as System clock source */
/******************************************************************************/
uint8_t SetSysClock_PLL_HSE(uint8_t bypass)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct;
RCC_OscInitTypeDef RCC_OscInitStruct;
#if (DEVICE_USBDEVICE)
RCC_PeriphCLKInitTypeDef RCC_PeriphCLKInit;
#endif /* DEVICE_USBDEVICE */
// Select HSI as system clock source to allow modification of the PLL configuration
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0);
/* Enable HSE oscillator and activate PLL with HSE as source */
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
if (bypass == 0) {
RCC_OscInitStruct.HSEState = RCC_HSE_ON; /* External xtal on OSC_IN/OSC_OUT */
} else {
RCC_OscInitStruct.HSEState = RCC_HSE_BYPASS; /* External 8 MHz clock on OSC_IN */
}
RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1; // 8 MHz external xtal (8 MHz = 8 MHz / 1)
#if (HSE_VALUE == 16000000)
RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV2; // 16 MHz external xtal (8 MHz = 16 MHz / 2)
#endif
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9; // 72 MHz (8 MHz * 9)
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
return 0; // FAIL
}
/* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers */
RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK; // 72 MHz
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; // 72 MHz
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2; // 36 MHz
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1; // 72 MHz
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK) {
return 0; // FAIL
}
#if (DEVICE_USBDEVICE)
/* USB clock selection */
RCC_PeriphCLKInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
RCC_PeriphCLKInit.UsbClockSelection = RCC_USBCLKSOURCE_PLL_DIV1_5;
HAL_RCCEx_PeriphCLKConfig(&RCC_PeriphCLKInit);
#endif /* DEVICE_USBDEVICE */
/* Output clock on MCO1 pin(PA8) for debugging purpose */
//HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSE, RCC_MCODIV_1); // 8 MHz
return 1; // OK
}
#endif /* ((CLOCK_SOURCE) & USE_PLL_HSE_XTAL) || ((CLOCK_SOURCE) & USE_PLL_HSE_EXTC) */
#if ((CLOCK_SOURCE) & USE_PLL_HSI)
/******************************************************************************/
/* PLL (clocked by HSI) used as System clock source */
/******************************************************************************/
uint8_t SetSysClock_PLL_HSI(void)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct;
RCC_OscInitTypeDef RCC_OscInitStruct;
#if (DEVICE_USBDEVICE)
RCC_PeriphCLKInitTypeDef RCC_PeriphCLKInit;
#endif /* DEVICE_USBDEVICE */
/* Enable HSI oscillator and activate PLL with HSI as source */
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI | RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSEState = RCC_HSE_OFF;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI_DIV2;
#if (DEVICE_USBDEVICE)
RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL12; // 48 MHz (8 MHz/2 * 12)
#else /* DEVICE_USBDEVICE */
RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL16; // 64 MHz (8 MHz/2 * 16)
#endif /* DEVICE_USBDEVICE */
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
return 0; // FAIL
}
#if (DEVICE_USBDEVICE)
/* USB clock selection */
RCC_PeriphCLKInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
RCC_PeriphCLKInit.UsbClockSelection = RCC_USBCLKSOURCE_PLL;
HAL_RCCEx_PeriphCLKConfig(&RCC_PeriphCLKInit);
#endif /* DEVICE_USBDEVICE */
/* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers */
RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK; // 64 MHz
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; // 64 MHz
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2; // 32 MHz
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1; // 64 MHz
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK) {
return 0; // FAIL
}
/* Output clock on MCO1 pin(PA8) for debugging purpose */
//HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSI, RCC_MCODIV_1); // 8 MHz
return 1; // OK
}
#endif /* ((CLOCK_SOURCE) & USE_PLL_HSI) */
