Refactoring GPIO, clock, and peripheral init

Inc/interrupts.h

@@ -0,0 +1,8 @@
+#ifndef __STM32F0xx_IT_H
+#define __STM32F0xx_IT_H
+
+void USB_IRQHandler(void);
+void SysTick_Handler(void);
+
+#endif 
+

Inc/led.h

@@ -4,6 +4,7 @@
 
 #define LED_DURATION 50
 
+void led_init();
 void led_on(void);
 void led_process(void);
 

Inc/stm32f0xx_it.h

@@ -1,58 +0,0 @@
-/**
-  ******************************************************************************
-  * @file    stm32f0xx_it.h
-  * @date    05/12/2014 20:22:27
-  * @brief   This file contains the headers of the interrupt handlers.
-  ******************************************************************************
-  *
-  * COPYRIGHT(c) 2014 STMicroelectronics
-  *
-  * Redistribution and use in source and binary forms, with or without modification,
-  * are permitted provided that the following conditions are met:
-  *   1. Redistributions of source code must retain the above copyright notice,
-  *      this list of conditions and the following disclaimer.
-  *   2. Redistributions in binary form must reproduce the above copyright notice,
-  *      this list of conditions and the following disclaimer in the documentation
-  *      and/or other materials provided with the distribution.
-  *   3. Neither the name of STMicroelectronics nor the names of its contributors
-  *      may be used to endorse or promote products derived from this software
-  *      without specific prior written permission.
-  *
-  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
-  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
-  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
-  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
-  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-  *
-  ******************************************************************************
-  */
-
-/* Define to prevent recursive inclusion -------------------------------------*/
-#ifndef __STM32F0xx_IT_H
-#define __STM32F0xx_IT_H
-
-#ifdef __cplusplus
- extern "C" {
-#endif 
-
-/* Includes ------------------------------------------------------------------*/
-/* Exported types ------------------------------------------------------------*/
-/* Exported constants --------------------------------------------------------*/
-/* Exported macro ------------------------------------------------------------*/
-/* Exported functions ------------------------------------------------------- */
-
-void USB_IRQHandler(void);
-void SysTick_Handler(void);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* __STM32F0xx_IT_H */
-
-/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

Inc/system.h

@@ -0,0 +1,8 @@
+#ifndef _SYSTEM_H
+#define _SYSTEM_H
+
+
+void system_init(void);
+
+
+#endif

Makefile

@@ -11,7 +11,7 @@
 BUILD_NUMBER ?= 0
 
 # SOURCES: list of sources in the user application
-SOURCES = main.c usbd_conf.c usbd_cdc_if.c usb_device.c usbd_desc.c stm32f0xx_hal_msp.c stm32f0xx_it.c system_stm32f0xx.c can.c slcan.c led.c
+SOURCES = main.c system.c usbd_conf.c usbd_cdc_if.c usb_device.c usbd_desc.c interrupts.c system_stm32f0xx.c can.c slcan.c led.c
 
 # TARGET: name of the user application
 TARGET = CANtact-b$(BUILD_NUMBER)

Src/can.c

@@ -1,7 +1,12 @@
+//
+// can: initializes and provides methods to interact with the CAN peripheral
+//
+
 #include "stm32f0xx_hal.h"
 #include "can.h"
 #include "led.h"
 
+
 CAN_HandleTypeDef hcan;
 CAN_FilterConfTypeDef filter;
 uint32_t prescaler;
@@ -11,6 +16,23 @@ enum can_bus_state bus_state;
 // Initialize CAN peripheral settings, but don't actually start the peripheral
 void can_init(void)
 {
+
+    // Initialize GPIO for CAN transceiver 
+    GPIO_InitTypeDef GPIO_InitStruct;
+    __CAN_CLK_ENABLE();
+    __GPIOB_CLK_ENABLE();
+
+    //PB8     ------> CAN_RX
+    //PB9     ------> CAN_TX
+    GPIO_InitStruct.Pin = GPIO_PIN_8|GPIO_PIN_9;
+    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
+    GPIO_InitStruct.Pull = GPIO_NOPULL;
+    GPIO_InitStruct.Speed = GPIO_SPEED_LOW;
+    GPIO_InitStruct.Alternate = GPIO_AF4_CAN;
+    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
+
+
+    // Initialize default CAN filter configuration
     filter.FilterIdHigh = 0;
     filter.FilterIdLow = 0;
     filter.FilterMaskIdHigh = 0;

Src/interrupts.c

@@ -4,7 +4,7 @@
 
 #include "stm32f0xx_hal.h"
 #include "stm32f0xx.h"
-#include "stm32f0xx_it.h"
+#include "interrupts.h"
 
 extern PCD_HandleTypeDef hpcd_USB_FS;
 

Src/led.c

@@ -8,6 +8,21 @@
 static uint32_t led_laston = 0;
 static uint32_t led_lastoff = 0;
 
+
+// Initialize LED GPIOs
+void led_init()
+{
+    __GPIOB_CLK_ENABLE();
+    GPIO_InitTypeDef GPIO_InitStruct;
+    GPIO_InitStruct.Pin = GPIO_PIN_0 | GPIO_PIN_1;
+    GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
+    GPIO_InitStruct.Pull = GPIO_PULLUP;
+    GPIO_InitStruct.Speed = GPIO_SPEED_MEDIUM;
+    GPIO_InitStruct.Alternate = 0;
+    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
+}
+
+
 // Attempt to turn on status LED
 void led_on(void)
 {

Src/main.c

@@ -8,26 +8,14 @@
 #include "usbd_cdc_if.h"
 #include "can.h"
 #include "slcan.h"
+#include "system.h"
 #include "led.h"
 
 
-void SystemClock_Config(void);
-static void MX_GPIO_Init(void);
-static void led_init(void);
-
-
-volatile int i=0;
 int main(void)
 {
-
-    /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
     HAL_Init();
-
+    system_init();
-    /* Configure the system clock */
-    SystemClock_Config();
-
-    /* Initialize all configured peripherals */
-    MX_GPIO_Init();
     can_init();
     led_init();
     MX_USB_DEVICE_Init();
@@ -44,12 +32,11 @@ int main(void)
 	HAL_Delay(100);
     HAL_GPIO_WritePin(GPIOB, GPIO_PIN_1, GPIO_PIN_RESET);
 
-    // loop forever
     CanRxMsgTypeDef rx_msg;
     uint32_t status;
     uint8_t msg_buf[SLCAN_MTU];
 
-
+    // loop forever
     for (;;) {
 		while (!is_can_msg_pending(CAN_FIFO0))
 			led_process();
@@ -60,125 +47,5 @@ int main(void)
 		}
 		led_process();
     }
-
 }
 
-void SystemClock_Config(void)
-{
-
-    RCC_OscInitTypeDef RCC_OscInitStruct;
-    RCC_ClkInitTypeDef RCC_ClkInitStruct;
-    RCC_PeriphCLKInitTypeDef PeriphClkInit;
-
-#ifdef INTERNAL_OSCILLATOR
-    // set up the oscillators
-    // use internal HSI48 (48 MHz), no PLL
-    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48;
-    RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
-    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
-
-    // set sysclk, hclk, and pclk1 source to HSI48 (48 MHz)
-    RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK |
-				   RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1);
-    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI48;
-    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
-    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
-
-    // set USB clock source to HSI48 (48 MHz)
-    PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
-    PeriphClkInit.UsbClockSelection = RCC_USBCLKSOURCE_HSI48;
-
-
-#else
-    // set up the oscillators
-    // use external oscillator (16 MHz), enable 3x PLL (48 MHz)
-    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
-    RCC_OscInitStruct.HSEState = RCC_HSE_ON;
-    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
-    RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
-    RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL3;
-    RCC_OscInitStruct.PLL.PREDIV = RCC_PREDIV_DIV1;
-
-    // set sysclk, hclk, and pclk1 source to PLL (48 MHz)
-    RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK |
-				   RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1);
-    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
-    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
-    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
-
-    // set USB clock source to PLL (48 MHz)
-    PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
-    PeriphClkInit.UsbClockSelection = RCC_USBCLKSOURCE_PLLCLK;
-
-#endif
-
-    HAL_RCC_OscConfig(&RCC_OscInitStruct);
-    HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0);
-    HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit);
-    __SYSCFG_CLK_ENABLE();
-
-
-	HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);
-	HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);
-    HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
-
-
-#ifdef INTERNAL_OSCILLATOR
-    // Enable clock recovery system for internal oscillator
-    RCC_CRSInitTypeDef RCC_CRSInitStruct;
-
-    // Enable CRS Clock
-    __CRS_CLK_ENABLE();
-
-    // Default Synchro Signal division factor (not divided) 
-    RCC_CRSInitStruct.Prescaler = RCC_CRS_SYNC_DIV1;
-
-    // Set the SYNCSRC[1:0] bits according to CRS_Source value 
-    RCC_CRSInitStruct.Source = RCC_CRS_SYNC_SOURCE_USB;
-
-    // HSI48 is synchronized with USB SOF at 1KHz rate 
-    RCC_CRSInitStruct.ReloadValue = __HAL_RCC_CRS_CALCULATE_RELOADVALUE(48000000, 1000);
-    RCC_CRSInitStruct.ErrorLimitValue = RCC_CRS_ERRORLIMIT_DEFAULT;
-
-    // Set the TRIM[5:0] to the default value
-    RCC_CRSInitStruct.HSI48CalibrationValue = 0x20; 
-
-    // Start automatic synchronization 
-    HAL_RCCEx_CRSConfig(&RCC_CRSInitStruct);
-
-    // Force sync event
-    HAL_RCCEx_CRSSoftwareSynchronizationGenerate();
-
-    // Wait until synchronized
-    HAL_RCCEx_CRSWaitSynchronization(3000);
-#endif
-
-}
-
-/** Configure pins as
- * Analog
- * Input
- * Output
- * EVENT_OUT
- * EXTI
- */
-void MX_GPIO_Init(void)
-{
-
-    /* GPIO Ports Clock Enable */
-    __GPIOF_CLK_ENABLE();
-    __GPIOA_CLK_ENABLE();
-    __GPIOB_CLK_ENABLE();
-}
-
-/* USER CODE BEGIN 4 */
-static void led_init()
-{
-    GPIO_InitTypeDef GPIO_InitStruct;
-    GPIO_InitStruct.Pin = GPIO_PIN_0 | GPIO_PIN_1;
-    GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
-    GPIO_InitStruct.Pull = GPIO_PULLUP;
-    GPIO_InitStruct.Speed = GPIO_SPEED_MEDIUM;
-    GPIO_InitStruct.Alternate = 0;
-    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
-}

Src/stm32f0xx_hal_msp.c

@@ -1,48 +0,0 @@
-#include "stm32f0xx_hal.h"
-
-void HAL_MspInit(void)
-{
-  HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
-}
-
-void HAL_CAN_MspInit(CAN_HandleTypeDef* hcan)
-{
-
-  GPIO_InitTypeDef GPIO_InitStruct;
-  if(hcan->Instance==CAN)
-  {
-    /* Peripheral clock enable */
-    __CAN_CLK_ENABLE();
-
-    /**CAN GPIO Configuration
-    PB8     ------> CAN_RX
-    PB9     ------> CAN_TX
-    */
-    GPIO_InitStruct.Pin = GPIO_PIN_8|GPIO_PIN_9;
-    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
-    GPIO_InitStruct.Pull = GPIO_NOPULL;
-    GPIO_InitStruct.Speed = GPIO_SPEED_LOW;
-    GPIO_InitStruct.Alternate = GPIO_AF4_CAN;
-    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
-
-  }
-
-}
-
-void HAL_CAN_MspDeInit(CAN_HandleTypeDef* hcan)
-{
-
-  if(hcan->Instance==CAN)
-  {
-    /* Peripheral clock disable */
-    __CAN_CLK_DISABLE();
-
-    /**CAN GPIO Configuration
-    PB8     ------> CAN_RX
-    PB9     ------> CAN_TX
-    */
-    HAL_GPIO_DeInit(GPIOB, GPIO_PIN_8|GPIO_PIN_9);
-
-  }
-
-}

Src/system.c

@@ -0,0 +1,105 @@
+//
+// system: initalize system clocks and other core peripherals
+//
+
+#include "stm32f0xx_hal.h"
+#include "system.h"
+
+
+// Initialize system clocks
+void system_init(void)
+{
+
+    RCC_OscInitTypeDef RCC_OscInitStruct;
+    RCC_ClkInitTypeDef RCC_ClkInitStruct;
+    RCC_PeriphCLKInitTypeDef PeriphClkInit;
+
+#ifdef INTERNAL_OSCILLATOR
+    // set up the oscillators
+    // use internal HSI48 (48 MHz), no PLL
+    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48;
+    RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
+    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
+
+    // set sysclk, hclk, and pclk1 source to HSI48 (48 MHz)
+    RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK |
+				   RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1);
+    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI48;
+    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
+    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
+
+    // set USB clock source to HSI48 (48 MHz)
+    PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
+    PeriphClkInit.UsbClockSelection = RCC_USBCLKSOURCE_HSI48;
+
+
+#else
+    // set up the oscillators
+    // use external oscillator (16 MHz), enable 3x PLL (48 MHz)
+    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
+    RCC_OscInitStruct.HSEState = RCC_HSE_ON;
+    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
+    RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
+    RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL3;
+    RCC_OscInitStruct.PLL.PREDIV = RCC_PREDIV_DIV1;
+
+    // set sysclk, hclk, and pclk1 source to PLL (48 MHz)
+    RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK |
+				   RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1);
+    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
+    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
+    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
+
+    // set USB clock source to PLL (48 MHz)
+    PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
+    PeriphClkInit.UsbClockSelection = RCC_USBCLKSOURCE_PLLCLK;
+
+#endif
+
+    HAL_RCC_OscConfig(&RCC_OscInitStruct);
+    HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0);
+    HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit);
+    __SYSCFG_CLK_ENABLE();
+
+
+	HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);
+	HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);
+    HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
+
+
+#ifdef INTERNAL_OSCILLATOR
+    // Enable clock recovery system for internal oscillator
+    RCC_CRSInitTypeDef RCC_CRSInitStruct;
+
+    // Enable CRS Clock
+    __CRS_CLK_ENABLE();
+
+    // Default Synchro Signal division factor (not divided) 
+    RCC_CRSInitStruct.Prescaler = RCC_CRS_SYNC_DIV1;
+
+    // Set the SYNCSRC[1:0] bits according to CRS_Source value 
+    RCC_CRSInitStruct.Source = RCC_CRS_SYNC_SOURCE_USB;
+
+    // HSI48 is synchronized with USB SOF at 1KHz rate 
+    RCC_CRSInitStruct.ReloadValue = __HAL_RCC_CRS_CALCULATE_RELOADVALUE(48000000, 1000);
+    RCC_CRSInitStruct.ErrorLimitValue = RCC_CRS_ERRORLIMIT_DEFAULT;
+
+    // Set the TRIM[5:0] to the default value
+    RCC_CRSInitStruct.HSI48CalibrationValue = 0x20; 
+
+    // Start automatic synchronization 
+    HAL_RCCEx_CRSConfig(&RCC_CRSInitStruct);
+
+    // Force sync event
+    HAL_RCCEx_CRSSoftwareSynchronizationGenerate();
+
+    // Wait until synchronized
+    HAL_RCCEx_CRSWaitSynchronization(3000);
+#endif
+
+    HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
+    __GPIOF_CLK_ENABLE();
+    __GPIOA_CLK_ENABLE();
+    __GPIOB_CLK_ENABLE();
+}
+

Src/usbd_conf.c

@@ -35,6 +35,7 @@
 /* Includes ------------------------------------------------------------------*/
 #include "stm32f0xx.h"
 #include "stm32f0xx_hal.h"
+#include "system.h"
 #include "usbd_def.h"
 #include "usbd_core.h"
 /* Private typedef -----------------------------------------------------------*/
@@ -502,7 +503,7 @@ void USBD_static_free(void *p)
   */
 static void SystemClockConfig_Resume(void)
 {
-	SystemClock_Config();
+    system_init();
 }
 /* USER CODE END 4 */