view Common/Drivers/STM32F4xx/Include/system_stm32f4xx.h @ 224:ceecabfddb57 div-fixes-3

Bugfix, deco: fix 2 (small) problems with calculated ceiling This fixes 1 trivial, and 1 not really trivial bug in the calculation of the ceiling. When simulating a bounce dive to 80m, things become clear (tried this on a CCR dive, fixed setpoint 1.2bar, about 15 minutes of bottom time). Closely watch the behavior of the ceiling data. At some point during the ascent, the ceiling begins to decrease in 10cm steps. Then suddenly (while still ascending), the ceiling increases again with 1m, does not change for some time, and then suddenly steps 1.1m less deep. While not very relevant to real deco diving, it is simply wrong. The reason for this is subtle. The algorithm used to find the ceiling is a sort of linear search, stepping down a meter, overshoot the depth, and search back in 10cm steps. It seems some numerical instability. Fixing this, was a bit more computational intensive search by stepping up down in equal steps of 10cm. But, I'm pretty sure that things can be speeded up here, as a ceiling does not change fast, so it should be not that difficult to limit the search space, or use a binary search algorithm instead. The trivial second problem fixed, is that the ceiling ends at the surface and not at 1m depth. This small issue became visible after changing the step down size above. Signed-off-by: Jan Mulder <jlmulder@xs4all.nl>
author Jan Mulder <jlmulder@xs4all.nl>
date Sun, 31 Mar 2019 19:35:51 +0200
parents c78bcbd5deda
children 4e10a3e087a1
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/**
  ******************************************************************************
  * @file    system_stm32f4xx.h
  * @author  MCD Application Team
  * @brief   CMSIS Cortex-M4 Device System Source File for STM32F4xx devices.       
  ******************************************************************************  
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT(c) 2017 STMicroelectronics</center></h2>
  *
  * 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.
  *
  ******************************************************************************  
  */ 

/** @addtogroup CMSIS
  * @{
  */

/** @addtogroup stm32f4xx_system
  * @{
  */  
  
/**
  * @brief Define to prevent recursive inclusion
  */
#ifndef __SYSTEM_STM32F4XX_H
#define __SYSTEM_STM32F4XX_H

#ifdef __cplusplus
 extern "C" {
#endif 

/** @addtogroup STM32F4xx_System_Includes
  * @{
  */

/**
  * @}
  */


/** @addtogroup STM32F4xx_System_Exported_types
  * @{
  */
  /* This variable is updated in three ways:
      1) by calling CMSIS function SystemCoreClockUpdate()
      2) by calling HAL API function HAL_RCC_GetSysClockFreq()
      3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency 
         Note: If you use this function to configure the system clock; then there
               is no need to call the 2 first functions listed above, since SystemCoreClock
               variable is updated automatically.
  */
extern uint32_t SystemCoreClock;          /*!< System Clock Frequency (Core Clock) */

extern const uint8_t  AHBPrescTable[16];    /*!< AHB prescalers table values */
extern const uint8_t  APBPrescTable[8];     /*!< APB prescalers table values */

/**
  * @}
  */

/** @addtogroup STM32F4xx_System_Exported_Constants
  * @{
  */

/**
  * @}
  */

/** @addtogroup STM32F4xx_System_Exported_Macros
  * @{
  */

/**
  * @}
  */

/** @addtogroup STM32F4xx_System_Exported_Functions
  * @{
  */
  
extern void SystemInit(void);
extern void SystemCoreClockUpdate(void);
/**
  * @}
  */

#ifdef __cplusplus
}
#endif

#endif /*__SYSTEM_STM32F4XX_H */

/**
  * @}
  */
  
/**
  * @}
  */  
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/