/*
* Copyright (c) 2015 - 2019, Nordic Semiconductor ASA
* All rights reserved.
*
* 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 the copyright holder 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.
*/
#ifndef NRFX_SAADC_H__
#define NRFX_SAADC_H__
#include <nrfx.h>
#include <hal/nrf_saadc.h>
#ifdef __cplusplus
extern "C" {
#endif
/**
* @defgroup nrfx_saadc SAADC driver
* @{
* @ingroup nrf_saadc
* @brief Successive Approximation Analog-to-Digital Converter (SAADC) peripheral driver.
*/
/** @brief Value to be set as high limit to disable limit detection. */
#define NRFX_SAADC_LIMITH_DISABLED (2047)
/** @brief Value to be set as low limit to disable limit detection. */
#define NRFX_SAADC_LIMITL_DISABLED (-2048)
/** @brief Macro for setting @ref nrfx_saadc_config_t to default settings. */
#define NRFX_SAADC_DEFAULT_CONFIG \
{ \
.resolution = (nrf_saadc_resolution_t)NRFX_SAADC_CONFIG_RESOLUTION, \
.oversample = (nrf_saadc_oversample_t)NRFX_SAADC_CONFIG_OVERSAMPLE, \
.interrupt_priority = NRFX_SAADC_CONFIG_IRQ_PRIORITY, \
.low_power_mode = NRFX_SAADC_CONFIG_LP_MODE \
}
/**
* @brief Macro for setting @ref nrf_saadc_channel_config_t to default settings
* in single-ended mode.
*
* @param PIN_P Analog input.
*/
#define NRFX_SAADC_DEFAULT_CHANNEL_CONFIG_SE(PIN_P) \
{ \
.resistor_p = NRF_SAADC_RESISTOR_DISABLED, \
.resistor_n = NRF_SAADC_RESISTOR_DISABLED, \
.gain = NRF_SAADC_GAIN1_6, \
.reference = NRF_SAADC_REFERENCE_INTERNAL, \
.acq_time = NRF_SAADC_ACQTIME_10US, \
.mode = NRF_SAADC_MODE_SINGLE_ENDED, \
.burst = NRF_SAADC_BURST_DISABLED, \
.pin_p = (nrf_saadc_input_t)(PIN_P), \
.pin_n = NRF_SAADC_INPUT_DISABLED \
}
/**
* @brief Macro for setting @ref nrf_saadc_channel_config_t to default settings
* in differential mode.
*
* @param PIN_P Positive analog input.
* @param PIN_N Negative analog input.
*/
#define NRFX_SAADC_DEFAULT_CHANNEL_CONFIG_DIFFERENTIAL(PIN_P, PIN_N) \
{ \
.resistor_p = NRF_SAADC_RESISTOR_DISABLED, \
.resistor_n = NRF_SAADC_RESISTOR_DISABLED, \
.gain = NRF_SAADC_GAIN1_6, \
.reference = NRF_SAADC_REFERENCE_INTERNAL, \
.acq_time = NRF_SAADC_ACQTIME_10US, \
.mode = NRF_SAADC_MODE_DIFFERENTIAL, \
.burst = NRF_SAADC_BURST_DISABLED, \
.pin_p = (nrf_saadc_input_t)(PIN_P), \
.pin_n = (nrf_saadc_input_t)(PIN_N) \
}
/** @brief SAADC driver configuration structure. */
typedef struct
{
nrf_saadc_resolution_t resolution; ///< Resolution configuration.
nrf_saadc_oversample_t oversample; ///< Oversampling configuration.
uint8_t interrupt_priority; ///< Interrupt priority.
bool low_power_mode; ///< Indicates if low power mode is active.
} nrfx_saadc_config_t;
/** @brief SAADC driver event types. */
typedef enum
{
NRFX_SAADC_EVT_DONE, ///< Event generated when the buffer is filled with samples.
NRFX_SAADC_EVT_LIMIT, ///< Event generated after one of the limits is reached.
NRFX_SAADC_EVT_CALIBRATEDONE ///< Event generated when the calibration is complete.
} nrfx_saadc_evt_type_t;
/** @brief SAADC driver done event data. */
typedef struct
{
nrf_saadc_value_t * p_buffer; ///< Pointer to buffer with converted samples.
uint16_t size; ///< Number of samples in the buffer.
} nrfx_saadc_done_evt_t;
/** @brief SAADC driver limit event data. */
typedef struct
{
uint8_t channel; ///< Channel on which the limit was detected.
nrf_saadc_limit_t limit_type; ///< Type of limit detected.
} nrfx_saadc_limit_evt_t;
/** @brief SAADC driver event structure. */
typedef struct
{
nrfx_saadc_evt_type_t type; ///< Event type.
union
{
nrfx_saadc_done_evt_t done; ///< Data for @ref NRFX_SAADC_EVT_DONE event.
nrfx_saadc_limit_evt_t limit; ///< Data for @ref NRFX_SAADC_EVT_LIMIT event.
} data; ///< Union to store event data.
} nrfx_saadc_evt_t;
/**
* @brief SAADC driver event handler.
*
* @param[in] p_event Pointer to an SAADC driver event. The event structure is allocated on
* the stack, so it is valid only within the context of the event handler.
*/
typedef void (* nrfx_saadc_event_handler_t)(nrfx_saadc_evt_t const * p_event);
/**
* @brief Function for initializing the SAADC.
*
* @param[in] p_config Pointer to the structure with initial configuration.
* @param[in] event_handler Event handler provided by the user.
* Must not be NULL.
*
* @retval NRFX_SUCCESS Initialization was successful.
* @retval NRFX_ERROR_INVALID_STATE The driver is already initialized.
*/
nrfx_err_t nrfx_saadc_init(nrfx_saadc_config_t const * p_config,
nrfx_saadc_event_handler_t event_handler);
/**
* @brief Function for uninitializing the SAADC.
*
* This function stops all ongoing conversions and disables all channels.
*/
void nrfx_saadc_uninit(void);
/**
* @brief Function for getting the address of a SAMPLE SAADC task.
*
* @return Task address.
*/
uint32_t nrfx_saadc_sample_task_get(void);
/**
* @brief Function for initializing an SAADC channel.
*
* This function configures and enables the channel.
*
* @param[in] channel Channel index.
* @param[in] p_config Pointer to the structure with the initial configuration.
*
* @retval NRFX_SUCCESS Initialization was successful.
* @retval NRFX_ERROR_INVALID_STATE The SAADC was not initialized.
* @retval NRFX_ERROR_NO_MEM The specified channel was already allocated.
*/
nrfx_err_t nrfx_saadc_channel_init(uint8_t channel,
nrf_saadc_channel_config_t const * const p_config);
/**
* @brief Function for uninitializing an SAADC channel.
*
* @param[in] channel Channel index.
*
* @retval NRFX_SUCCESS Uninitialization was successful.
* @retval NRFX_ERROR_BUSY The SAADC is busy.
*/
nrfx_err_t nrfx_saadc_channel_uninit(uint8_t channel);
/**
* @brief Function for starting the SAADC sampling.
*
* @retval NRFX_SUCCESS The SAADC sampling was triggered.
* @retval NRFX_ERROR_INVALID_STATE The SAADC is in idle state.
*/
nrfx_err_t nrfx_saadc_sample(void);
/**
* @brief Blocking function for executing a single SAADC conversion.
*
* This function selects the desired input, starts a single conversion,
* waits for it to finish, and returns the result.
*
* The function fails if the SAADC is busy.
*
* @param[in] channel Channel.
* @param[out] p_value Pointer to the location where the result is to be placed.
*
* @retval NRFX_SUCCESS The conversion was successful.
* @retval NRFX_ERROR_BUSY The SAADC driver is busy.
*/
nrfx_err_t nrfx_saadc_sample_convert(uint8_t channel, nrf_saadc_value_t * p_value);
/**
* @brief Function for issuing conversion of data to the buffer.
*
* This function is non-blocking. The application is notified about filling the buffer by the event
* handler. Conversion will be done on all enabled channels. If the SAADC is in idle state, the
* function will set up EasyDMA for the conversion. The SAADC will be ready for sampling and wait
* for the SAMPLE task. It can be triggered manually by the @ref nrfx_saadc_sample function
* or by PPI using the @ref NRF_SAADC_TASK_SAMPLE task. If one buffer is already set and the
* conversion is ongoing, calling this function will result in queuing the given buffer.
* The driver will start filling the issued buffer when the first one is completed.
* If the function is called again before the first buffer is filled or calibration
* is in progress, it will return with error.
*
* @param[in] buffer Result buffer.
* @param[in] size Buffer size in words.
*
* @retval NRFX_SUCCESS The conversion was successful.
* @retval NRFX_ERROR_BUSY The driver already has two buffers set or the calibration is in progress.
*/
nrfx_err_t nrfx_saadc_buffer_convert(nrf_saadc_value_t * buffer, uint16_t size);
/**
* @brief Function for triggering the SAADC offset calibration.
*
* This function is non-blocking. The application is notified about completion by the event handler.
* Calibration will also trigger DONE and RESULTDONE events.
*
* The function will fail if the SAADC is busy or calibration is already in progress.
*
* @retval NRFX_SUCCESS The calibration was started successfully.
* @retval NRFX_ERROR_BUSY The SAADC driver is busy.
*/
nrfx_err_t nrfx_saadc_calibrate_offset(void);
/**
* @brief Function for retrieving the SAADC state.
*
* @retval true The SAADC is busy.
* @retval false The SAADC is ready.
*/
bool nrfx_saadc_is_busy(void);
/**
* @brief Function for aborting the ongoing and buffered conversions.
*
* @note @ref NRFX_SAADC_EVT_DONE event will be generated if there is a conversion in progress.
* Event will contain number of words in the sample buffer.
*/
void nrfx_saadc_abort(void);
/**
* @brief Function for setting the SAADC channel limits.
* When limits are enabled and the result exceeds the defined bounds, the limit handler
* function is called.
*
* @param[in] channel SAADC channel number.
* @param[in] limit_low Lower limit (valid values from @ref NRFX_SAADC_LIMITL_DISABLED to
* @ref NRFX_SAADC_LIMITH_DISABLED). Conversion results below this value will
* trigger the handler function. Set to @ref NRFX_SAADC_LIMITL_DISABLED
* to disable this limit.
* @param[in] limit_high Upper limit (valid values from @ref NRFX_SAADC_LIMITL_DISABLED to
* @ref NRFX_SAADC_LIMITH_DISABLED). Conversion results above this value will
* trigger the handler function. Set to @ref NRFX_SAADC_LIMITH_DISABLED
* to disable this limit.
*/
void nrfx_saadc_limits_set(uint8_t channel, int16_t limit_low, int16_t limit_high);
/** @} */
void nrfx_saadc_irq_handler(void);
#ifdef __cplusplus
}
#endif
#endif // NRFX_SAADC_H__