Bare-metal configuration for a Bluepill board.
Warning
It does not work with the Mbed Online Compiler.
Follow these steps to import and compile them with Mbed CLI:
mbed import https://os.mbed.com/users/hudakz/code/Baremetal_Blinky_Bluepill mbed compile -t GCC_ARM -m bluepill
TARGET_BLUEPILL/device/system_clock.c
- Committer:
- hudakz
- Date:
- 2020-05-14
- Revision:
- 0:a04710facbb6
File content as of revision 0:a04710facbb6:
/* mbed Microcontroller Library * Copyright (c) 2006-2017 ARM Limited * * 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 | 3- PLL_HSI * | (external 8 MHz clock) | (internal 8 MHz) * | 2- PLL_HSE_XTAL | * | (external 8 MHz xtal) | *----------------------------------------------------------------------------- * SYSCLK(MHz) | 72 | 64 *----------------------------------------------------------------------------- * AHBCLK (MHz) | 72 | 64 *----------------------------------------------------------------------------- * APB1CLK (MHz) | 36 | 32 *----------------------------------------------------------------------------- * APB2CLK (MHz) | 72 | 64 *----------------------------------------------------------------------------- * USB capable (48 MHz precise clock) | NO | NO *----------------------------------------------------------------------------- ****************************************************************************** */ #include "stm32f1xx.h" /*!< Uncomment the following line if you need to relocate your vector Table in Internal SRAM. */ /* #define VECT_TAB_SRAM */ #define VECT_TAB_OFFSET 0x00000000U /*!< Vector Table base offset field. This value must be a multiple of 0x200. */ /* Select the clock sources (other than HSI) to start with (0=OFF, 1=ON) */ #define USE_PLL_HSE_EXTC (0) /* Use external clock */ #define USE_PLL_HSE_XTAL (1) /* Use external xtal */ #if (USE_PLL_HSE_XTAL != 0) || (USE_PLL_HSE_EXTC != 0) uint8_t SetSysClock_PLL_HSE(uint8_t bypass); #endif uint8_t SetSysClock_PLL_HSI(void); /** * @brief Setup the microcontroller system * Initialize the Embedded Flash Interface, the PLL and update the * SystemCoreClock variable. * @note This function should be used only after reset. * @param None * @retval None */ void SystemInit (void) { /* Reset the RCC clock configuration to the default reset state(for debug purpose) */ /* Set HSION bit */ RCC->CR |= 0x00000001U; /* Reset SW, HPRE, PPRE1, PPRE2, ADCPRE and MCO bits */ #if !defined(STM32F105xC) && !defined(STM32F107xC) RCC->CFGR &= 0xF8FF0000U; #else RCC->CFGR &= 0xF0FF0000U; #endif /* STM32F105xC */ /* Reset HSEON, CSSON and PLLON bits */ RCC->CR &= 0xFEF6FFFFU; /* Reset HSEBYP bit */ RCC->CR &= 0xFFFBFFFFU; /* Reset PLLSRC, PLLXTPRE, PLLMUL and USBPRE/OTGFSPRE bits */ RCC->CFGR &= 0xFF80FFFFU; #if defined(STM32F105xC) || defined(STM32F107xC) /* Reset PLL2ON and PLL3ON bits */ RCC->CR &= 0xEBFFFFFFU; /* Disable all interrupts and clear pending bits */ RCC->CIR = 0x00FF0000U; /* Reset CFGR2 register */ RCC->CFGR2 = 0x00000000U; #elif defined(STM32F100xB) || defined(STM32F100xE) /* Disable all interrupts and clear pending bits */ RCC->CIR = 0x009F0000U; /* Reset CFGR2 register */ RCC->CFGR2 = 0x00000000U; #else /* Disable all interrupts and clear pending bits */ RCC->CIR = 0x009F0000U; #endif /* STM32F105xC */ #if defined(STM32F100xE) || defined(STM32F101xE) || defined(STM32F101xG) || defined(STM32F103xE) || defined(STM32F103xG) #ifdef DATA_IN_ExtSRAM SystemInit_ExtMemCtl(); #endif /* DATA_IN_ExtSRAM */ #endif #ifdef VECT_TAB_SRAM SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM. */ #else SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH. */ #endif } /** * @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) { /* 1- Try to start with HSE and external clock */ #if USE_PLL_HSE_EXTC != 0 if (SetSysClock_PLL_HSE(1) == 0) #endif { /* 2- If fail try to start with HSE and external xtal */ #if USE_PLL_HSE_XTAL != 0 if (SetSysClock_PLL_HSE(0) == 0) #endif { /* 3- If fail start with HSI clock */ if (SetSysClock_PLL_HSI() == 0) { while(1) { // [TODO] Put something here to tell the user that a problem occured... } } } } /* 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 (USE_PLL_HSE_XTAL != 0) || (USE_PLL_HSE_EXTC != 0) /******************************************************************************/ /* 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; /* 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 8 MHz 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; 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 } /* 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 /******************************************************************************/ /* PLL (clocked by HSI) used as System clock source */ /******************************************************************************/ uint8_t SetSysClock_PLL_HSI(void) { RCC_ClkInitTypeDef RCC_ClkInitStruct; RCC_OscInitTypeDef RCC_OscInitStruct; /* 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; RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL16; // 64 MHz (8 MHz/2 * 16) 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; // 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 }