tool/mbed/mbed-sdk/libraries/mbed/targets/cmsis/TARGET_STM/TARGET_STM32L0/TARGET_NUCLEO_L053R8/hal_tick.c

   1 /**
   2   ******************************************************************************
   3   * @file    hal_tick.c
   4   * @author  MCD Application Team
   5   * @brief   Initialization of HAL tick
   6   ******************************************************************************
   7   * @attention
   8   *
   9   * <h2><center>&copy; COPYRIGHT 2014 STMicroelectronics</center></h2>
  10   *
  11   * Redistribution and use in source and binary forms, with or without modification,
  12   * are permitted provided that the following conditions are met:
  13   *   1. Redistributions of source code must retain the above copyright notice,
  14   *      this list of conditions and the following disclaimer.
  15   *   2. Redistributions in binary form must reproduce the above copyright notice,
  16   *      this list of conditions and the following disclaimer in the documentation
  17   *      and/or other materials provided with the distribution.
  18   *   3. Neither the name of STMicroelectronics nor the names of its contributors
  19   *      may be used to endorse or promote products derived from this software
  20   *      without specific prior written permission.
  21   *
  22   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  23   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  25   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  26   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  28   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  29   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32   *
  33   ******************************************************************************
  34   */
  35 #include "hal_tick.h"
  36
  37 TIM_HandleTypeDef TimMasterHandle;
  38 uint32_t PreviousVal = 0;
  39
  40 void us_ticker_irq_handler(void);
  41 void set_compare(uint16_t count);
  42
  43 extern volatile uint32_t SlaveCounter;
  44 extern volatile uint32_t oc_int_part;
  45 extern volatile uint16_t oc_rem_part;
  46
  47 void timer_irq_handler(void) {
  48     uint16_t cval = TIM_MST->CNT;
  49
  50     TimMasterHandle.Instance = TIM_MST;
  51
  52     // Clear Update interrupt flag
  53     if (__HAL_TIM_GET_FLAG(&TimMasterHandle, TIM_FLAG_UPDATE) == SET) {
  54         __HAL_TIM_CLEAR_FLAG(&TimMasterHandle, TIM_FLAG_UPDATE);
  55         SlaveCounter++;
  56     }
  57
  58     // Channel 1 for mbed timeout
  59     if (__HAL_TIM_GET_FLAG(&TimMasterHandle, TIM_FLAG_CC1) == SET) {
  60         __HAL_TIM_CLEAR_FLAG(&TimMasterHandle, TIM_FLAG_CC1);
  61         if (oc_rem_part > 0) {
  62             set_compare(oc_rem_part); // Finish the remaining time left
  63             oc_rem_part = 0;
  64         } else {
  65             if (oc_int_part > 0) {
  66                 set_compare(0xFFFF);
  67                 oc_rem_part = cval; // To finish the counter loop the next time
  68                 oc_int_part--;
  69             } else {
  70                 us_ticker_irq_handler();
  71             }
  72         }
  73     }
  74
  75     // Channel 2 for HAL tick
  76     if (__HAL_TIM_GET_FLAG(&TimMasterHandle, TIM_FLAG_CC2) == SET) {
  77         __HAL_TIM_CLEAR_FLAG(&TimMasterHandle, TIM_FLAG_CC2);
  78         uint32_t val = __HAL_TIM_GetCounter(&TimMasterHandle);
  79         if ((val - PreviousVal) >= HAL_TICK_DELAY) {
  80             // Increment HAL variable
  81             HAL_IncTick();
  82             // Prepare next interrupt
  83             __HAL_TIM_SetCompare(&TimMasterHandle, TIM_CHANNEL_2, val + HAL_TICK_DELAY);
  84             PreviousVal = val;
  85         }
  86     }
  87 }
  88
  89 // Reconfigure the HAL tick using a standard timer instead of systick.
  90 HAL_StatusTypeDef HAL_InitTick(uint32_t TickPriority) {
  91     // Enable timer clock
  92     TIM_MST_RCC;
  93
  94     // Reset timer
  95     TIM_MST_RESET_ON;
  96     TIM_MST_RESET_OFF;
  97
  98     // Update the SystemCoreClock variable
  99     SystemCoreClockUpdate();
 100
 101     // Configure time base
 102     TimMasterHandle.Instance = TIM_MST;
 103     TimMasterHandle.Init.Period        = 0xFFFFFFFF;
 104     TimMasterHandle.Init.Prescaler     = (uint32_t)(SystemCoreClock / 1000000) - 1; // 1 us tick
 105     TimMasterHandle.Init.ClockDivision = 0;
 106     TimMasterHandle.Init.CounterMode   = TIM_COUNTERMODE_UP;
 107     HAL_TIM_Base_Init(&TimMasterHandle);
 108
 109     // Configure output compare channel 1 for mbed timeout (enabled later when used)
 110     HAL_TIM_OC_Start(&TimMasterHandle, TIM_CHANNEL_1);
 111
 112     // Configure output compare channel 2 for HAL tick
 113     HAL_TIM_OC_Start(&TimMasterHandle, TIM_CHANNEL_2);
 114     PreviousVal = __HAL_TIM_GetCounter(&TimMasterHandle);
 115     __HAL_TIM_SetCompare(&TimMasterHandle, TIM_CHANNEL_2, PreviousVal + HAL_TICK_DELAY);
 116
 117     // Configure interrupts
 118     // Update interrupt used for 32-bit counter
 119     // Output compare channel 1 interrupt for mbed timeout
 120     // Output compare channel 2 interrupt for HAL tick
 121     NVIC_SetVector(TIM_MST_IRQ, (uint32_t)timer_irq_handler);
 122     NVIC_EnableIRQ(TIM_MST_IRQ);
 123
 124     // Enable interrupts
 125     __HAL_TIM_ENABLE_IT(&TimMasterHandle, TIM_IT_UPDATE); // For 32-bit counter
 126     __HAL_TIM_ENABLE_IT(&TimMasterHandle, TIM_IT_CC2); // For HAL tick
 127
 128     // Enable timer
 129     HAL_TIM_Base_Start(&TimMasterHandle);
 130
 131     return HAL_OK;
 132 }
 133
 134 /**
 135   * @}
 136   */
 137
 138 /**
 139   * @}
 140   */
 141
 142 /**
 143   * @}
 144   */
 145 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/