/** * Copyright (c) 2015 - 2018, 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, except as embedded into a Nordic * Semiconductor ASA integrated circuit in a product or a software update for * such product, 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 Nordic Semiconductor ASA nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * 4. This software, with or without modification, must only be used with a * Nordic Semiconductor ASA integrated circuit. * * 5. Any software provided in binary form under this license must not be reverse * engineered, decompiled, modified and/or disassembled. * * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA 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 #include #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 that should be set as high limit to disable limit detection. */ #define NRFX_SAADC_LIMITH_DISABLED (2047) /** * @brief Value that should 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, \ .pin_p = (nrf_saadc_input_t)(PIN_P), \ .pin_n = (nrf_saadc_input_t)(PIN_N) \ } /** * @brief Analog-to-digital converter 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 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 Analog-to-digital converter 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 Analog-to-digital converter 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 Analog-to-digital converter 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; } nrfx_saadc_evt_t; /** * @brief ADC event handler. * * @param[in] p_event Pointer to an ADC 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 If initialization was successful. * @retval NRFX_ERROR_INVALID_STATE If 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. * * @retval NRFX_SUCCESS If initialization was successful. * @retval NRFX_ERROR_INVALID_STATE If the ADC was not initialized. * @retval NRFX_ERROR_NO_MEM If 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. * * @retval NRFX_SUCCESS If uninitialization was successful. * @retval NRFX_ERROR_BUSY If the ADC is busy. */ nrfx_err_t nrfx_saadc_channel_uninit(uint8_t channel); /** * @brief Function for starting SAADC sampling. * * @retval NRFX_SUCCESS If ADC sampling was triggered. * @retval NRFX_ERROR_INVALID_STATE If ADC is in idle state. */ nrfx_err_t nrfx_saadc_sample(void); /** * @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. * * The function will fail if ADC is busy. * * @param[in] channel Channel. * @param[out] p_value Pointer to the location where the result should be placed. * * @retval NRFX_SUCCESS If conversion was successful. * @retval NRFX_ERROR_BUSY If the ADC 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 ADC is in idle state, the * function will set up Easy DMA for the conversion. The ADC 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 If conversion was successful. * @retval NRFX_ERROR_BUSY If the driver already has two buffers set or calibration is in progress. */ nrfx_err_t nrfx_saadc_buffer_convert(nrf_saadc_value_t * buffer, uint16_t size); /** * @brief Function for triggering the ADC 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 ADC is busy or calibration is already in progress. * * @retval NRFX_SUCCESS If calibration was started successfully. * @retval NRFX_ERROR_BUSY If the ADC driver is busy. */ nrfx_err_t nrfx_saadc_calibrate_offset(void); /** * @brief Function for retrieving the SAADC state. * * @retval true If the ADC is busy. * @retval false If the ADC is ready. */ bool nrfx_saadc_is_busy(void); /** * @brief Function for aborting 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__