text: /* Copyright (c) 2014 Nordic Semiconductor. All Rights Reserved.
   *
   * The information contained herein is property of Nordic Semiconductor ASA.
   * Terms and conditions of usage are described in detail in NORDIC
   * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
   *
   * Licensees are granted free, non-transferable use of the information. NO
   * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
   * the file.
   *
   */
  
  #ifndef NRF_ADC_H_
  #define NRF_ADC_H_
  
  /**
   * @defgroup nrf_adc_hal ADC HAL
   * @{
   * @ingroup nrf_adc
   * @brief @tagAPI51 Hardware access layer for managing the analog-to-digital converter (ADC).
   */
  
  #include <stdbool.h>
  #include <stddef.h>
  
  #include "nrf.h"
  
  #ifndef NRF52
  /**
   * @enum  nrf_adc_config_resolution_t
   * @brief Resolution of the analog-to-digital converter.
   */
  
  /**
   * @brief ADC interrupts.
   */
  typedef enum
  {
      NRF_ADC_INT_END_MASK  = ADC_INTENSET_END_Msk,   /**< ADC interrupt on END event. */
  } nrf_adc_int_mask_t;
  
  typedef enum
  {
      NRF_ADC_CONFIG_RES_8BIT  = ADC_CONFIG_RES_8bit,  /**< 8 bit resolution. */
      NRF_ADC_CONFIG_RES_9BIT  = ADC_CONFIG_RES_9bit,  /**< 9 bit resolution. */
      NRF_ADC_CONFIG_RES_10BIT = ADC_CONFIG_RES_10bit, /**< 10 bit resolution. */
  } nrf_adc_config_resolution_t;
  
  
  /**
   * @enum nrf_adc_config_scaling_t
   * @brief Scaling factor of the analog-to-digital conversion.
   */
  typedef enum
  {
      NRF_ADC_CONFIG_SCALING_INPUT_FULL_SCALE  = ADC_CONFIG_INPSEL_AnalogInputNoPrescaling,        /**< Full scale input. */
      NRF_ADC_CONFIG_SCALING_INPUT_TWO_THIRDS  = ADC_CONFIG_INPSEL_AnalogInputTwoThirdsPrescaling, /**< 2/3 scale input. */
      NRF_ADC_CONFIG_SCALING_INPUT_ONE_THIRD   = ADC_CONFIG_INPSEL_AnalogInputOneThirdPrescaling,  /**< 1/3 scale input. */
      NRF_ADC_CONFIG_SCALING_SUPPLY_TWO_THIRDS = ADC_CONFIG_INPSEL_SupplyTwoThirdsPrescaling,      /**< 2/3 of supply. */
      NRF_ADC_CONFIG_SCALING_SUPPLY_ONE_THIRD  = ADC_CONFIG_INPSEL_SupplyOneThirdPrescaling        /**< 1/3 of supply. */
  } nrf_adc_config_scaling_t;
  
  /**
   * @enum nrf_adc_config_reference_t
   * @brief Reference selection of the analog-to-digital converter.
   */
  typedef enum
  {
      NRF_ADC_CONFIG_REF_VBG              = ADC_CONFIG_REFSEL_VBG,                      /**< 1.2 V reference. */
      NRF_ADC_CONFIG_REF_SUPPLY_ONE_HALF  = ADC_CONFIG_REFSEL_SupplyOneHalfPrescaling,  /**< 1/2 of power supply. */
      NRF_ADC_CONFIG_REF_SUPPLY_ONE_THIRD = ADC_CONFIG_REFSEL_SupplyOneThirdPrescaling, /**< 1/3 of power supply. */
      NRF_ADC_CONFIG_REF_EXT_REF0         = ADC_CONFIG_REFSEL_External |
                                            ADC_CONFIG_EXTREFSEL_AnalogReference0 <<
      ADC_CONFIG_EXTREFSEL_Pos, /**< External reference 0. */
          NRF_ADC_CONFIG_REF_EXT_REF1 = ADC_CONFIG_REFSEL_External |
                                    ADC_CONFIG_EXTREFSEL_AnalogReference1 << ADC_CONFIG_EXTREFSEL_Pos, /**< External reference 0. */
  } nrf_adc_config_reference_t;
  
  /**
   * @enum nrf_adc_config_input_t
   * @brief Input selection of the analog-to-digital converter.
   */
  typedef enum
  {
      NRF_ADC_CONFIG_INPUT_DISABLED = ADC_CONFIG_PSEL_Disabled,     /**< No input selected. */
      NRF_ADC_CONFIG_INPUT_0        = ADC_CONFIG_PSEL_AnalogInput0, /**< Input 0. */
      NRF_ADC_CONFIG_INPUT_1        = ADC_CONFIG_PSEL_AnalogInput1, /**< Input 1. */
      NRF_ADC_CONFIG_INPUT_2        = ADC_CONFIG_PSEL_AnalogInput2, /**< Input 2. */
      NRF_ADC_CONFIG_INPUT_3        = ADC_CONFIG_PSEL_AnalogInput3, /**< Input 3. */
      NRF_ADC_CONFIG_INPUT_4        = ADC_CONFIG_PSEL_AnalogInput4, /**< Input 4. */
      NRF_ADC_CONFIG_INPUT_5        = ADC_CONFIG_PSEL_AnalogInput5, /**< Input 5. */
      NRF_ADC_CONFIG_INPUT_6        = ADC_CONFIG_PSEL_AnalogInput6, /**< Input 6. */
      NRF_ADC_CONFIG_INPUT_7        = ADC_CONFIG_PSEL_AnalogInput7, /**< Input 7. */
  } nrf_adc_config_input_t;
  
  /**
   * @enum nrf_adc_task_t
   * @brief Analog-to-digital converter tasks.
   */
  typedef enum
  {
      /*lint -save -e30*/
      NRF_ADC_TASK_START = offsetof(NRF_ADC_Type, TASKS_START), /**< ADC start sampling task. */
      NRF_ADC_TASK_STOP  = offsetof(NRF_ADC_Type, TASKS_STOP)   /**< ADC stop sampling task. */
      /*lint -restore*/
  } nrf_adc_task_t;
  
  /**
   * @enum nrf_adc_event_t
   * @brief Analog-to-digital converter events.
   */
  typedef enum /*lint -save -e30 -esym(628,__INTADDR__) */
  {
      /*lint -save -e30*/
      NRF_ADC_EVENT_END = offsetof(NRF_ADC_Type, EVENTS_END) /**< End of conversion event. */
      /*lint -restore*/
  } nrf_adc_event_t;
  
  /**@brief Analog-to-digital converter configuration. */
  typedef struct
  {
      nrf_adc_config_resolution_t resolution; /**< ADC resolution. */
      nrf_adc_config_scaling_t    scaling;    /**< ADC scaling factor. */
      nrf_adc_config_reference_t  reference;  /**< ADC reference. */
  } nrf_adc_config_t;
  
  /** Default ADC configuration. */
  #define NRF_ADC_CONFIG_DEFAULT { NRF_ADC_CONFIG_RES_10BIT,               \
                                   NRF_ADC_CONFIG_SCALING_INPUT_ONE_THIRD, \
                                   NRF_ADC_CONFIG_REF_VBG }
  
  /**
   * @brief Function for configuring ADC.
   *
   * This function powers on the analog-to-digital converter and configures it. 
   * After the configuration, the ADC is in DISABLE state and must be
   * enabled before using it.
   *
   * @param[in] config Configuration parameters.
   */
  void nrf_adc_configure(nrf_adc_config_t * config);
  
  /**
   * @brief Blocking function for executing a single ADC conversion.
   *
   * This function selects the desired input, starts a single conversion,
   * waits for it to finish, and returns the result.
   * After the input is selected, the analog-to-digital converter
   * is left in STOP state.
   * The function does not check if the ADC is initialized and powered.
   *
   * @param[in] input Input to be selected.
   *
   * @return Conversion result.
   */
  int32_t nrf_adc_convert_single(nrf_adc_config_input_t input);
  
  /**
   * @brief Function for selecting ADC input.
   *
   * This function selects the active input of ADC. Ensure that
   * the ADC is powered on and in IDLE state before calling this function.
   *
   * @param[in] input Input to be selected.
   */
  __STATIC_INLINE void nrf_adc_input_select(nrf_adc_config_input_t input)
  {
      NRF_ADC->CONFIG =
          ((uint32_t)input << ADC_CONFIG_PSEL_Pos) | (NRF_ADC->CONFIG & ~ADC_CONFIG_PSEL_Msk);
  
      if (input != NRF_ADC_CONFIG_INPUT_DISABLED)
      {
          NRF_ADC->ENABLE = ADC_ENABLE_ENABLE_Enabled << ADC_ENABLE_ENABLE_Pos;
      }
      else
      {
          NRF_ADC->ENABLE = ADC_ENABLE_ENABLE_Disabled << ADC_ENABLE_ENABLE_Pos;
      }
  }
  
  
  /**
   * @brief Function for retrieving the ADC conversion result.
   *
   * This function retrieves and returns the last analog-to-digital conversion result.
   *
   * @return Last conversion result.
   */
  __STATIC_INLINE int32_t nrf_adc_result_get(void)
  {
      return (int32_t)NRF_ADC->RESULT;
  }
  
  
  /**
   * @brief Function for checking whether the ADC is busy.
   *
   * This function checks whether the analog-to-digital converter is busy with a conversion.
   *
   * @retval true If the ADC is busy.
   * @retval false If the ADC is not busy.
   */
  __STATIC_INLINE bool nrf_adc_is_busy(void)
  {
      return ( (NRF_ADC->BUSY & ADC_BUSY_BUSY_Msk) == ADC_BUSY_BUSY_Msk);
  }
  
  /**
   * @brief Function for getting the ADC's enabled interrupts.
   *
   * @param[in] mask Mask of interrupts to check.
   *
   * @return State of the interrupts selected by the mask.
   *
   * @sa nrf_adc_int_enable()
   * @sa nrf_adc_int_disable()
   */
  __STATIC_INLINE uint32_t nrf_adc_int_get(uint32_t mask)
  {
      return (NRF_ADC->INTENSET & mask); // when read this register will return the value of INTEN.
  }
  
  
  /**
   * @brief Function for starting conversion.
   *
   * @sa nrf_adc_stop()
   *
   */
  __STATIC_INLINE void nrf_adc_start(void)
  {
      NRF_ADC->TASKS_START = 1;
  }
  
  
  /**
   * @brief Function for stopping conversion. 
   *
   * If the analog-to-digital converter is in inactive state, power consumption is reduced.
   *
   * @sa nrf_adc_start()
   *
   */
  __STATIC_INLINE void nrf_adc_stop(void)
  {
      NRF_ADC->TASKS_STOP = 1;
  }
  
  
  /**
   * @brief Function for checking if the requested ADC conversion has ended.
   *
   * @retval true If the task has finished.
   * @retval false If the task is still running.
   */
  __STATIC_INLINE bool nrf_adc_conversion_finished(void)
  {
      return ((bool)NRF_ADC->EVENTS_END);
  }
  
  /**
   * @brief Function for clearing the conversion END event.
   */
  __STATIC_INLINE void nrf_adc_conversion_event_clean(void)
  {
      NRF_ADC->EVENTS_END = 0;
  }
  
  /**
   * @brief Function for getting the address of an ADC task register.
   *
   * @param[in] adc_task ADC task.
   *
   * @return Address of the specified ADC task.
   */
  __STATIC_INLINE uint32_t nrf_adc_task_address_get(nrf_adc_task_t adc_task);
  
  /**
   * @brief Function for getting the address of a specific ADC event register.
   *
   * @param[in] adc_event ADC event.
   *
   * @return Address of the specified ADC event.
   */
  __STATIC_INLINE uint32_t nrf_adc_event_address_get(nrf_adc_event_t adc_event);
  
  /**
   * @brief Function for setting the CONFIG register in ADC.
   *
   * @param[in] configuration Value to be written to the CONFIG register.
   */
  __STATIC_INLINE void nrf_adc_config_set(uint32_t configuration);
  
  /**
   * @brief Function for clearing an ADC event.
   *
   * @param[in] event Event to clear.
   */
  __STATIC_INLINE void nrf_adc_event_clear(nrf_adc_event_t event);
  
  /**
   * @brief Function for checking state of an ADC event.
   *
   * @param[in] event Event to check.
   *
   * @retval true  If the event is set.
   * @retval false If the event is not set.
   */
  __STATIC_INLINE bool nrf_adc_event_check(nrf_adc_event_t event);
  
  /**
   * @brief Function for enabling specified interrupts.
   *
   * @param[in] int_mask  Interrupts to enable.
   */
  __STATIC_INLINE void nrf_adc_int_enable(uint32_t int_mask);
  
  /**
   * @brief Function for disabling specified interrupts.
   *
   * @param[in] int_mask  Interrupts to disable.
   */
  __STATIC_INLINE void nrf_adc_int_disable(uint32_t int_mask);
  
  /**
   * @brief Function for retrieving the state of a given interrupt.
   *
   * @param[in] int_mask Interrupt to check.
   *
   * @retval true  If the interrupt is enabled.
   * @retval false If the interrupt is not enabled.
   */
  __STATIC_INLINE bool nrf_adc_int_enable_check(nrf_adc_int_mask_t int_mask);
  
  /**
   * @brief Function for activating a specific ADC task.
   *
   * @param[in] task Task to activate.
   */
  __STATIC_INLINE void nrf_adc_task_trigger(nrf_adc_task_t task);
  
  /**
   * @brief Function for enabling ADC.
   *
   */
  __STATIC_INLINE void nrf_adc_enable(void);
  
  /**
   * @brief Function for disabling ADC.
   *
   */
  __STATIC_INLINE void nrf_adc_disable(void);
  
  #ifndef SUPPRESS_INLINE_IMPLEMENTATION
  
  __STATIC_INLINE uint32_t nrf_adc_task_address_get(nrf_adc_task_t adc_task)
  {
      return (uint32_t)((uint8_t *)NRF_ADC + adc_task);
  }
  
  __STATIC_INLINE uint32_t nrf_adc_event_address_get(nrf_adc_event_t adc_event)
  {
      return (uint32_t)((uint8_t *)NRF_ADC + adc_event);
  }
  
  __STATIC_INLINE void nrf_adc_config_set(uint32_t configuration)
  {
      NRF_ADC->CONFIG = configuration;
  }
  
  __STATIC_INLINE void nrf_adc_event_clear(nrf_adc_event_t event)
  {
      *((volatile uint32_t *)((uint8_t *)NRF_ADC + (uint32_t)event)) = 0x0UL;
  }
  
  __STATIC_INLINE bool nrf_adc_event_check(nrf_adc_event_t event)
  {
      return (bool)*(volatile uint32_t *)((uint8_t *)NRF_ADC + (uint32_t)event);
  }
  
  __STATIC_INLINE void nrf_adc_int_enable(uint32_t int_mask)
  {
      NRF_ADC->INTENSET = int_mask;
  }
  
  __STATIC_INLINE void nrf_adc_int_disable(uint32_t int_mask)
  {
      NRF_ADC->INTENCLR = int_mask;
  }
  
  __STATIC_INLINE bool nrf_adc_int_enable_check(nrf_adc_int_mask_t int_mask)
  {
      return (bool)(NRF_ADC->INTENSET & int_mask);
  }
  
  __STATIC_INLINE void nrf_adc_task_trigger(nrf_adc_task_t task)
  {
      *((volatile uint32_t *)((uint8_t *)NRF_ADC + (uint32_t)task)) = 0x1UL;
  }
  
  __STATIC_INLINE void nrf_adc_enable(void)
  {
      NRF_ADC->ENABLE = 1;
  }
  
  __STATIC_INLINE void nrf_adc_disable(void)
  {
      NRF_ADC->ENABLE = 0;
  }
  #endif
  #endif /* NRF52 */
  /**
   *@}
   **/
  
  #endif /* NRF_ADC_H_ */
  