AMiRo-OS

/************************************************************************************//**

* \file         Demo\ARMCM3_STM32_Olimex_STM32P103_GCC\Boot\main.c

* \brief        Bootloader application source file.

* \ingroup      Boot_ARMCM3_STM32_Olimex_STM32P103_GCC

* \internal

*----------------------------------------------------------------------------------------

*                          C O P Y R I G H T

*----------------------------------------------------------------------------------------

*   Copyright (c) 2012  by Feaser    http://www.feaser.com    All rights reserved

*

*----------------------------------------------------------------------------------------

*                            L I C E N S E

*----------------------------------------------------------------------------------------

* This file is part of OpenBLT. OpenBLT is free software: you can redistribute it and/or

* modify it under the terms of the GNU General Public License as published by the Free

* Software Foundation, either version 3 of the License, or (at your option) any later

* version.

*

* OpenBLT is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;

* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR

* PURPOSE. See the GNU General Public License for more details.

*

* You should have received a copy of the GNU General Public License along with OpenBLT.

* If not, see <http://www.gnu.org/licenses/>.

*

* A special exception to the GPL is included to allow you to distribute a combined work

* that includes OpenBLT without being obliged to provide the source code for any

* proprietary components. The exception text is included at the bottom of the license

* file <license.html>.

*

* \endinternal

****************************************************************************************/

/****************************************************************************************

* Include files

****************************************************************************************/

#include "boot.h"                                /* bootloader generic header          */

#include "stm32f10x.h"                           /* microcontroller registers          */

#include "stm32f10x_conf.h"                      /* STM32 peripheral drivers           */

#include "timer.h"

#include "ARMCM3_STM32/types.h"

#include "AMiRo/amiroblt.h"

#include "AMiRo/helper.h"

/****************************************************************************************

* Defines

****************************************************************************************/

#define WKUP_GPIO           GPIOA

#define WKUP_PIN            GPIO_Pin_0

#define LED_GPIO            GPIOA

#define LED_PIN             GPIO_Pin_1

#define DRIVE_PWM1A_GPIO    GPIOA

#define DRIVE_PWM1A_PIN     GPIO_Pin_2

#define DRIVE_PWM1B_GPIO    GPIOA

#define DRIVE_PWM1B_PIN     GPIO_Pin_3

#define MOTION_SCLK_GPIO    GPIOA

#define MOTION_SCLK_PIN     GPIO_Pin_5

#define MOTION_MISO_GPIO    GPIOA

#define MOTION_MISO_PIN     GPIO_Pin_6

#define MOTION_MOSI_GPIO    GPIOA

#define MOTION_MOSI_PIN     GPIO_Pin_7

#define PROG_RX_GPIO        GPIOA

#define PROG_RX_PIN         GPIO_Pin_9

#define PROG_TX_GPIO        GPIOA

#define PROG_TX_PIN         GPIO_Pin_10

#define CAN_RX_GPIO         GPIOA

#define CAN_RX_PIN          GPIO_Pin_11

#define CAN_TX_GPIO         GPIOA

#define CAN_TX_PIN          GPIO_Pin_12

#define SWDIO_GPIO          GPIOA

#define SWDIO_PIN           GPIO_Pin_13

#define SWCLK_GPIO          GPIOA

#define SWCLK_PIN           GPIO_Pin_14

#define DRIVE_PWM2B_GPIO    GPIOA

#define DRIVE_PWM2B_PIN     GPIO_Pin_15

#define DRIVE_SENSE2_GPIO   GPIOB

#define DRIVE_SENSE2_PIN    GPIO_Pin_1

#define POWER_EN_GPIO       GPIOB

#define POWER_EN_PIN        GPIO_Pin_2

#define DRIVE_PWM2A_GPIO    GPIOB

#define DRIVE_PWM2A_PIN     GPIO_Pin_3

#define COMPASS_DRDY_GPIO   GPIOB

#define COMPASS_DRDY_PIN    GPIO_Pin_5

#define DRIVE_ENC1A_GPIO    GPIOB

#define DRIVE_ENC1A_PIN     GPIO_Pin_6

#define DRIVE_ENC1B_GPIO    GPIOB

#define DRIVE_ENC1B_PIN     GPIO_Pin_7

#define COMPASS_SCL_GPIO    GPIOB

#define COMPASS_SCL_PIN     GPIO_Pin_8

#define COMPASS_SDA_GPIO    GPIOB

#define COMPASS_SDA_PIN     GPIO_Pin_9

#define IR_SCL_GPIO         GPIOB

#define IR_SCL_PIN          GPIO_Pin_10

#define IR_SDA_GPIO         GPIOB

#define IR_SDA_PIN          GPIO_Pin_11

#define IR_INT_GPIO         GPIOB

#define IR_INT_PIN          GPIO_Pin_12

#define GYRP_DRDY_GPIO      GPIOB

#define GYRO_DRDY_PIN       GPIO_Pin_13

#define SYS_UART_UP_GPIO    GPIOB

#define SYS_UART_UP_PIN     GPIO_Pin_14

#define ACCEL_INT_N_GPIO    GPIOB

#define ACCEL_INT_N_PIN     GPIO_Pin_15

#define DRIVE_SENSE1_GPIO   GPIOC

#define DRIVE_SENSE1_PIN    GPIO_Pin_0

#define SYS_SYNC_N_GPIO     GPIOC

#define SYS_SYNC_N_PIN      GPIO_Pin_1

#define PATH_DCSTAT_GPIO    GPIOC

#define PATH_DCSTAT_PIN     GPIO_Pin_3

#define PATH_DCEN_GPIO      GPIOC

#define PATH_DCEN_PIN       GPIO_Pin_5

#define DRIVE_ENC2B_GPIO    GPIOC

#define DRIVE_ENC2B_PIN     GPIO_Pin_6

#define DRIVE_ENC2A_GPIO    GPIOC

#define DRIVE_ENC2A_PIN     GPIO_Pin_7

#define SYS_PD_N_GPIO       GPIOC

#define SYS_PD_N_PIN        GPIO_Pin_8

#define SYS_REG_EN_GPIO     GPIOC

#define SYS_REG_EN_PIN      GPIO_Pin_9

#define SYS_UART_RX_GPIO    GPIOC

#define SYS_UART_RX_PIN     GPIO_Pin_10

#define SYS_UART_TX_GPIO    GPIOC

#define SYS_UART_TX_PIN     GPIO_Pin_11

#define ACCEL_SS_N_GPIO     GPIOC

#define ACCEL_SS_N_PIN      GPIO_Pin_13

#define GYRO_SS_N_GPIO      GPIOC

#define GYRO_SS_N_PIN       GPIO_Pin_14

#define OSC_IN_GPIO         GPIOD

#define OSC_IN_PIN          GPIO_Pin_0

#define OSC_OUT_GPIO        GPIOD

#define OSC_OUT_PIN         GPIO_Pin_1

#define SYS_WARMRST_N_GPIO  GPIOD

#define SYS_WARMRST_N_PIN   GPIO_Pin_2

#define RESET_TIMEOUT_MS    100

/****************************************************************************************

* Function prototypes

****************************************************************************************/

static void Init(void);

static void initGpio();

static void initExti();

void configGpioForShutdown();

ErrorStatus handleColdReset();

ErrorStatus handleUartWakeup();

ErrorStatus handleAccelWakeup();

ErrorStatus shutdownDisambiguationProcedure(const uint8_t type);

void shutdownToTransportation(const blt_bool exec_disambiguation);

void shutdownToDeepsleep(const blt_bool exec_disambiguation);

void shutdownToHibernate(const blt_bool exec_disambiguation);

void shutdownAndRestart(const blt_bool exec_disambiguation);

volatile blBackupRegister_t backup_reg;

/****************************************************************************************

* Callback configuration

****************************************************************************************/

void blCallbackShutdownTransportation(void);

void blCallbackShutdownDeepsleep(void);

void blCallbackShutdownHibernate(void);

void blCallbackShutdownRestart(void);

void blCallbackHandleShutdownRequest(void);

const blCallbackTable_t cbtable __attribute__ ((section ("_callback_table"))) = {

  .magicNumber = BL_MAGIC_NUMBER,

  .vBootloader = {BL_VERSION_ID_AMiRoBLT_Release, BL_VERSION_MAJOR, BL_VERSION_MINOR, 1},

  .vSSSP = {BL_VERSION_ID_SSSP, SSSP_VERSION_MAJOR, SSSP_VERSION_MINOR, 0},

  .vCompiler = {BL_VERSION_ID_GCC, __GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__},  // currently only GCC is supported

  .cbShutdownHibernate = blCallbackShutdownHibernate,

  .cbShutdownDeepsleep = blCallbackShutdownDeepsleep,

  .cbShutdownTransportation = blCallbackShutdownTransportation,

  .cbShutdownRestart = blCallbackShutdownRestart,

  .cbHandleShutdownRequest = blCallbackHandleShutdownRequest,

  .cb5 = (void*)0,

  .cb6 = (void*)0,

  .cb7 = (void*)0,

  .cb8 = (void*)0,

  .cb9 = (void*)0,

  .cb10 = (void*)0,

  .cb11 = (void*)0

};

/************************************************************************************//**

** \brief     This is the entry point for the bootloader application and is called

**            by the reset interrupt vector after the C-startup routines executed.

** \return    Program return code.

**

****************************************************************************************/

int main(void)

{

  /* initialize the microcontroller */

  Init();

  /* activate some required clocks */

  RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE);

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC | RCC_APB2Periph_GPIOD, ENABLE);

  /* initialize GPIOs and EXTI lines */

  initGpio();

  setLed(BLT_TRUE);

  initExti();

  /* initialize the timer */

  TimerInit();

  /* detect the primary reason for this wakeup/restart */

  backup_reg.wakeup_pri_reason =

      ((RCC_GetFlagStatus(RCC_FLAG_LPWRRST) == SET) ? BL_WAKEUP_PRI_RSN_LPWRRST : 0) |

      ((RCC_GetFlagStatus(RCC_FLAG_WWDGRST) == SET) ? BL_WAKEUP_PRI_RSN_WWDGRST : 0) |

      ((RCC_GetFlagStatus(RCC_FLAG_IWDGRST) == SET) ? BL_WAKEUP_PRI_RSN_IWDGRST : 0) |

      ((RCC_GetFlagStatus(RCC_FLAG_SFTRST) == SET) ? BL_WAKEUP_PRI_RSN_SFTRST : 0)   |

      ((RCC_GetFlagStatus(RCC_FLAG_PORRST) == SET) ? BL_WAKEUP_PRI_RSN_PORRST : 0)   |

      ((RCC_GetFlagStatus(RCC_FLAG_PINRST) == SET) ? BL_WAKEUP_PRI_RSN_PINRST : 0)   |

      ((PWR_GetFlagStatus(PWR_FLAG_WU) == SET) ? BL_WAKEUP_PRI_RSN_WKUP : 0);

  /* when woken from standby mode, detect the secondary reason for thiswakeup/reset */

  if ( (backup_reg.wakeup_pri_reason & BL_WAKEUP_PRI_RSN_WKUP) && (PWR_GetFlagStatus(PWR_FLAG_SB) == SET) ) {

    if (GPIO_ReadInputDataBit(SYS_UART_UP_GPIO, SYS_UART_UP_PIN) == Bit_SET) {

      backup_reg.wakeup_sec_reason = BL_WAKEUP_SEC_RSN_UART;

    } else {

      backup_reg.wakeup_sec_reason = BL_WAKEUP_SEC_RSN_ACCEL;

    }

  } else {

    backup_reg.wakeup_sec_reason = BL_WAKEUP_SEC_RSN_UNKNOWN;

  }

  /* clear the flags */

  RCC_ClearFlag();

  PWR_ClearFlag(PWR_FLAG_WU);

  setLed(BLT_FALSE);

  /* wait 1ms for all signals to become stable */

  msleep(1);

  /* handle different wakeup/reset reasons */

  ErrorStatus status = ERROR;

  if (backup_reg.wakeup_pri_reason & BL_WAKEUP_PRI_RSN_WKUP) {

    /* the system was woken via WKUP pin */

    /* differenciate between two wakeup types */

    switch (backup_reg.wakeup_sec_reason) {

      case BL_WAKEUP_SEC_RSN_UART:

        status = handleUartWakeup();

        break;

      case BL_WAKEUP_SEC_RSN_ACCEL:

        status = handleAccelWakeup();

        break;

      default:

        status = ERROR;

        break;

    }

  } else if (backup_reg.wakeup_pri_reason & BL_WAKEUP_PRI_RSN_PINRST) {

    /* system was woken via NRST pin */

    status = handleColdReset();

  } else {

    /* system was woken/reset for an unexpected reason */

    blinkSOS(1);

    status = handleColdReset();

  }

  /* if something wehnt wrong, signal this failure */

  if (status != SUCCESS) {

    blinkSOSinf();

  }

  return 0;

} /*** end of main ***/

/************************************************************************************//**

** \brief     Initializes the microcontroller.

** \return    none.

**

****************************************************************************************/

static void Init(void)

{

  volatile blt_int32u StartUpCounter = 0, HSEStatus = 0;

  blt_int32u pll_multiplier;

#if (BOOT_FILE_LOGGING_ENABLE > 0) && (BOOT_COM_UART_ENABLE == 0)

  GPIO_InitTypeDef  GPIO_InitStruct;

  USART_InitTypeDef USART_InitStruct;

#endif

  /* reset the RCC clock configuration to the default reset state (for debug purpose) */

  /* set HSION bit */

  RCC->CR |= (blt_int32u)0x00000001;

  /* reset SW, HPRE, PPRE1, PPRE2, ADCPRE and MCO bits */

  RCC->CFGR &= (blt_int32u)0xF8FF0000;

  /* reset HSEON, CSSON and PLLON bits */

  RCC->CR &= (blt_int32u)0xFEF6FFFF;

  /* reset HSEBYP bit */

  RCC->CR &= (blt_int32u)0xFFFBFFFF;

  /* reset PLLSRC, PLLXTPRE, PLLMUL and USBPRE/OTGFSPRE bits */

  RCC->CFGR &= (blt_int32u)0xFF80FFFF;

  /* disable all interrupts and clear pending bits  */

  RCC->CIR = 0x009F0000;

  /* enable HSE */

  RCC->CR |= ((blt_int32u)RCC_CR_HSEON);

  /* wait till HSE is ready and if Time out is reached exit */

  do

  {

    HSEStatus = RCC->CR & RCC_CR_HSERDY;

    StartUpCounter++;

  }

  while((HSEStatus == 0) && (StartUpCounter != 1500));

  /* check if time out was reached */

  if ((RCC->CR & RCC_CR_HSERDY) == RESET)

  {

    /* cannot continue when HSE is not ready */

    ASSERT_RT(BLT_FALSE);

  }

  /* enable flash prefetch buffer */

  FLASH->ACR |= FLASH_ACR_PRFTBE;

  /* reset flash wait state configuration to default 0 wait states */

  FLASH->ACR &= (blt_int32u)((blt_int32u)~FLASH_ACR_LATENCY);

#if (BOOT_CPU_SYSTEM_SPEED_KHZ > 48000)

  /* configure 2 flash wait states */

  FLASH->ACR |= (blt_int32u)FLASH_ACR_LATENCY_2;

#elif (BOOT_CPU_SYSTEM_SPEED_KHZ > 24000)

  /* configure 1 flash wait states */

  FLASH->ACR |= (blt_int32u)FLASH_ACR_LATENCY_1;

#endif

  /* HCLK = SYSCLK */

  RCC->CFGR |= (blt_int32u)RCC_CFGR_HPRE_DIV1;

  /* PCLK2 = HCLK/2 */

  RCC->CFGR |= (blt_int32u)RCC_CFGR_PPRE2_DIV2;

  /* PCLK1 = HCLK/2 */

  RCC->CFGR |= (blt_int32u)RCC_CFGR_PPRE1_DIV2;

  /* reset PLL configuration */

  RCC->CFGR &= (blt_int32u)((blt_int32u)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLXTPRE | \

                                          RCC_CFGR_PLLMULL));

  /* assert that the pll_multiplier is between 2 and 16 */

  ASSERT_CT((BOOT_CPU_SYSTEM_SPEED_KHZ/BOOT_CPU_XTAL_SPEED_KHZ) >= 2);

  ASSERT_CT((BOOT_CPU_SYSTEM_SPEED_KHZ/BOOT_CPU_XTAL_SPEED_KHZ) <= 16);

  /* calculate multiplier value */

  pll_multiplier = BOOT_CPU_SYSTEM_SPEED_KHZ/BOOT_CPU_XTAL_SPEED_KHZ;

  /* convert to register value */

  pll_multiplier = (blt_int32u)((pll_multiplier - 2) << 18);

  /* set the PLL multiplier and clock source */

  RCC->CFGR |= (blt_int32u)(RCC_CFGR_PLLSRC_HSE | pll_multiplier);

  /* enable PLL */

  RCC->CR |= RCC_CR_PLLON;

  /* wait till PLL is ready */

  while((RCC->CR & RCC_CR_PLLRDY) == 0)

  {

  }

  /* select PLL as system clock source */

  RCC->CFGR &= (blt_int32u)((blt_int32u)~(RCC_CFGR_SW));

  RCC->CFGR |= (blt_int32u)RCC_CFGR_SW_PLL;

  /* wait till PLL is used as system clock source */

  while ((RCC->CFGR & (blt_int32u)RCC_CFGR_SWS) != (blt_int32u)0x08)

  {

  }

  /* remap JTAG pins */

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);

  AFIO->MAPR &= ~(blt_int32u)((blt_int32u)0x7 << 24);

  AFIO->MAPR |=  (blt_int32u)((blt_int32u)0x2 << 24);

  /* all input */

#if (BOOT_COM_CAN_ENABLE > 0 || BOOT_GATE_CAN_ENABLE > 0)

  /* enable clocks for CAN transmitter and receiver pins (GPIOB and AFIO) */

  RCC->APB2ENR |= (blt_int32u)(0x00000004 | 0x00000001);

  /* configure CAN Rx (GPIOA11) as alternate function input */

  /* first reset the configuration */

  GPIOA->CRH &= ~(blt_int32u)((blt_int32u)0xf << 12);

  /* CNF8[1:0] = %01 and MODE8[1:0] = %00 */

  GPIOA->CRH |= (blt_int32u)((blt_int32u)0x4 << 12);

  /* configure CAN Tx (GPIOA12) as alternate function push-pull */

  /* first reset the configuration */

  GPIOA->CRH &= ~(blt_int32u)((blt_int32u)0xf << 16);

  /* CNF9[1:0] = %11 and MODE9[1:0] = %11 */

  GPIOA->CRH |= (blt_int32u)((blt_int32u)0xb << 16);

  /* remap CAN1 pins to PortA */

  AFIO->MAPR &= ~(blt_int32u)((blt_int32u)0x3 << 13);

  AFIO->MAPR |=  (blt_int32u)((blt_int32u)0x0 << 13);

#endif

#if (BOOT_COM_UART_ENABLE > 0 || BOOT_GATE_UART_ENABLE > 0)

  /* enable clocks for USART1 peripheral, transmitter and receiver pins (GPIOA and AFIO) */

  RCC->APB2ENR |= (blt_int32u)(0x00004000 | 0x00000004 | 0x00000001);

  /* configure USART1 Tx (GPIOA9) as alternate function push-pull */

  /* first reset the configuration */

  GPIOA->CRH &= ~(blt_int32u)((blt_int32u)0xf << 4);

  /* CNF2[1:0] = %10 and MODE2[1:0] = %11 */

  GPIOA->CRH |= (blt_int32u)((blt_int32u)0xb << 4);

  /* configure USART1 Rx (GPIOA10) as alternate function input floating */

  /* first reset the configuration */

  GPIOA->CRH &= ~(blt_int32u)((blt_int32u)0xf << 8);

  /* CNF2[1:0] = %01 and MODE2[1:0] = %00 */

  GPIOA->CRH |= (blt_int32u)((blt_int32u)0x4 << 8);

#endif

} /*** end of Init ***/

/*

 * Initializes all GPIO used by the bootloader

 */

static void initGpio() {

  GPIO_InitTypeDef gpio_init;

  /*

   * OUTPUTS

   */

  /* initialize LED and push it up (inactive) */

  GPIO_SetBits(LED_GPIO, LED_PIN);

  gpio_init.GPIO_Pin    = LED_PIN;

  gpio_init.GPIO_Mode   = GPIO_Mode_Out_PP;

  gpio_init.GPIO_Speed  = GPIO_Speed_50MHz;

  GPIO_Init(LED_GPIO, &gpio_init);

  /* initialize SYS_PD_N and let it go (inactive) */

  GPIO_SetBits(SYS_PD_N_GPIO, SYS_PD_N_PIN);

  gpio_init.GPIO_Pin    = SYS_PD_N_PIN;

  gpio_init.GPIO_Mode   = GPIO_Mode_Out_OD;

  gpio_init.GPIO_Speed  = GPIO_Speed_50MHz;

  GPIO_Init(SYS_PD_N_GPIO, &gpio_init);

  /* initialize SYS_SYNC_N and pull it down (active) */

  GPIO_ResetBits(SYS_SYNC_N_GPIO, SYS_SYNC_N_PIN);

  gpio_init.GPIO_Pin    = SYS_SYNC_N_PIN;

  gpio_init.GPIO_Mode   = GPIO_Mode_Out_OD;

  gpio_init.GPIO_Speed  = GPIO_Speed_50MHz;

  GPIO_Init(SYS_SYNC_N_GPIO, &gpio_init);

  /* initialize SYS_WARMST_N and let it go (active) */

  GPIO_SetBits(SYS_WARMRST_N_GPIO, SYS_WARMRST_N_PIN);

  gpio_init.GPIO_Pin    = SYS_WARMRST_N_PIN;

  gpio_init.GPIO_Mode   = GPIO_Mode_Out_OD;

  gpio_init.GPIO_Speed  = GPIO_Speed_50MHz;

  GPIO_Init(SYS_WARMRST_N_GPIO, &gpio_init);

  /* initialize SYS_UART_UP and let it go (inactive) */

  GPIO_SetBits(SYS_UART_UP_GPIO, SYS_UART_UP_PIN);

  gpio_init.GPIO_Pin    = SYS_UART_UP_PIN;

  gpio_init.GPIO_Mode   = GPIO_Mode_Out_OD;

  gpio_init.GPIO_Speed  = GPIO_Speed_50MHz;

  GPIO_Init(SYS_UART_UP_GPIO, &gpio_init);

  /* initialize PATH_DCEN and pull it down (inactive) */

  GPIO_ResetBits(PATH_DCEN_GPIO, PATH_DCEN_PIN);

  gpio_init.GPIO_Pin    = PATH_DCEN_PIN;

  gpio_init.GPIO_Mode   = GPIO_Mode_Out_PP;

  gpio_init.GPIO_Speed  = GPIO_Speed_50MHz;

  GPIO_Init(PATH_DCEN_GPIO, &gpio_init);

  /*

   * INPUTS

   */

  /* initialize the input ACCEL_INT_N */

  gpio_init.GPIO_Pin    = ACCEL_INT_N_PIN;

  gpio_init.GPIO_Mode   = GPIO_Mode_IN_FLOATING;

  gpio_init.GPIO_Speed  = GPIO_Speed_50MHz;

  GPIO_Init(ACCEL_INT_N_GPIO, &gpio_init);

  return;

} /*** end of initGpio ***/

/*

 * Initialize all EXTI lines

 */

static void initExti() {

  /* configure EXTI lines */

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOC, GPIO_PinSource1); // SYS_SYNC_N

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOD, GPIO_PinSource2); // SYS_WARMRST_N

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOC, GPIO_PinSource3); // PATH_DCSTAT

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource5); // COMPASS_DRDY

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOC, GPIO_PinSource8); // SYS_PD_N

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOC, GPIO_PinSource9); // SYS_REG_EN

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource12); // IR_INT

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource13); // GYRO_DRDY

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource14); // SYS_UART_UP

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource15); // ACCEL_INT_N

  return;

}

/*

 * Signals, which type of low-power mode the system shall enter after the shutdown sequence.

 */

ErrorStatus shutdownDisambiguationProcedure(const uint8_t type) {

  GPIO_SetBits(SYS_SYNC_N_GPIO, SYS_SYNC_N_PIN);