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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_ADC_H__ #define NRFX_ADC_H__ #include #include #ifdef __cplusplus extern "C" { #endif /** * @defgroup nrfx_adc ADC driver * @{ * @ingroup nrf_adc * @brief Analog-to-Digital Converter (ADC) peripheral driver. */ /** * @brief Driver event types. */ typedef enum { NRFX_ADC_EVT_DONE, ///< Event generated when the buffer is filled with samples. NRFX_ADC_EVT_SAMPLE, ///< Event generated when the requested channel is sampled. } nrfx_adc_evt_type_t; /** * @brief Analog-to-digital converter driver DONE event. */ typedef struct { nrf_adc_value_t * p_buffer; ///< Pointer to the buffer with converted samples. uint16_t size; ///< Number of samples in the buffer. } nrfx_adc_done_evt_t; /** * @brief Analog-to-digital converter driver SAMPLE event. */ typedef struct { nrf_adc_value_t sample; ///< Converted sample. } nrfx_adc_sample_evt_t; /** * @brief Analog-to-digital converter driver event. */ typedef struct { nrfx_adc_evt_type_t type; ///< Event type. union { nrfx_adc_done_evt_t done; ///< Data for DONE event. nrfx_adc_sample_evt_t sample; ///< Data for SAMPLE event. } data; } nrfx_adc_evt_t; /**@brief Macro for initializing the ADC channel with the default configuration. */ #define NRFX_ADC_DEFAULT_CHANNEL(analog_input) \ { \ NULL, \ { \ .resolution = NRF_ADC_CONFIG_RES_10BIT, \ .scaling = NRF_ADC_CONFIG_SCALING_INPUT_FULL_SCALE, \ .reference = NRF_ADC_CONFIG_REF_VBG, \ .input = (analog_input), \ .extref = NRF_ADC_CONFIG_EXTREFSEL_NONE \ } \ } // Forward declaration of the nrfx_adc_channel_t type. typedef struct nrfx_adc_channel_s nrfx_adc_channel_t; /** * @brief ADC channel. * * This structure is defined by the user and used by the driver. Therefore, it should * not be defined on the stack as a local variable. */ struct nrfx_adc_channel_s { nrfx_adc_channel_t * p_next; ///< Pointer to the next enabled channel (for internal use). nrf_adc_config_t config; ///< ADC configuration for the current channel. }; /** * @brief ADC configuration. */ typedef struct { uint8_t interrupt_priority; ///< Priority of ADC interrupt. } nrfx_adc_config_t; /** @brief ADC default configuration. */ #define NRFX_ADC_DEFAULT_CONFIG \ { \ .interrupt_priority = NRFX_ADC_CONFIG_IRQ_PRIORITY \ } /** * @brief User event handler prototype. * * This function is called when the requested number of samples has been processed. * * @param p_event Event. */ typedef void (*nrfx_adc_event_handler_t)(nrfx_adc_evt_t const * p_event); /** * @brief Function for initializing the ADC. * * If a valid event handler is provided, the driver is initialized in non-blocking mode. * If event_handler is NULL, the driver works in blocking mode. * * @param[in] p_config Pointer to the structure with initial configuration. * @param[in] event_handler Event handler provided by the user. * * @retval NRFX_SUCCESS If initialization was successful. * @retval NRFX_ERROR_INVALID_STATE If the driver is already initialized. */ nrfx_err_t nrfx_adc_init(nrfx_adc_config_t const * p_config, nrfx_adc_event_handler_t event_handler); /** * @brief Function for uninitializing the ADC. * * This function stops all ongoing conversions and disables all channels. */ void nrfx_adc_uninit(void); /** * @brief Function for enabling an ADC channel. * * This function configures and enables the channel. When @ref nrfx_adc_buffer_convert is * called, all channels that have been enabled with this function are sampled. * * This function can be called only when there is no conversion in progress * (the ADC is not busy). * * @note The channel instance variable @p p_channel is used by the driver as an item * in a list. Therefore, it cannot be an automatic variable that is located on the stack. */ void nrfx_adc_channel_enable(nrfx_adc_channel_t * const p_channel); /** * @brief Function for disabling an ADC channel. * * This function can be called only when there is no conversion in progress * (the ADC is not busy). */ void nrfx_adc_channel_disable(nrfx_adc_channel_t * const p_channel); /** * @brief Function for disabling all ADC channels. * * This function can be called only when there is no conversion in progress * (the ADC is not busy). */ void nrfx_adc_all_channels_disable(void); /** * @brief Function for starting ADC sampling. * * This function triggers single ADC sampling. If more than one channel is enabled, the driver * emulates scanning and all channels are sampled in the order they were enabled. */ void nrfx_adc_sample(void); /** * @brief Function for executing a single ADC conversion. * * This function selects the desired input and starts a single conversion. If a valid pointer * is provided for the result, the function blocks until the conversion is completed. Otherwise, the * function returns when the conversion is started, and the result is provided in an event (driver * must be initialized in non-blocking mode, otherwise an assertion will fail). The function will * fail if ADC is busy. The channel does not need to be enabled to perform a single conversion. * * @param[in] p_channel Channel. * @param[out] p_value Pointer to the location where the result should be placed. Unless NULL is * provided, the function is blocking. * * @retval NRFX_SUCCESS If conversion was successful. * @retval NRFX_ERROR_BUSY If the ADC driver is busy. */ nrfx_err_t nrfx_adc_sample_convert(nrfx_adc_channel_t const * const p_channel, nrf_adc_value_t * p_value); /** * @brief Function for converting data to the buffer. * * If the driver is initialized in non-blocking mode, this function returns when the first * conversion is set up. When the buffer is filled, the application is notified by the event * handler. If the driver is initialized in blocking mode, the function returns when the buffer is * filled. * * Conversion is done on all enabled channels, but it is not triggered by this * function. This function will prepare the ADC for sampling and then * wait for the SAMPLE task. Sampling can be triggered manually by the @ref * nrfx_adc_sample function or by PPI using the @ref NRF_ADC_TASK_START task. * * @note If more than one channel is enabled, the function emulates scanning, and * a single START task will trigger conversion on all enabled channels. For example: * If 3 channels are enabled and the user requests 6 samples, the completion event * handler will be called after 2 START tasks. * * @note The application must adjust the sampling frequency. The maximum frequency * depends on the sampling timer and the maximum latency of the ADC interrupt. If * an interrupt is not handled before the next sampling is triggered, the sample * will be lost. * * @param[in] buffer Result buffer. * @param[in] size Buffer size in samples. * * @retval NRFX_SUCCESS If conversion was successful. * @retval NRFX_ERROR_BUSY If the driver is busy. */ nrfx_err_t nrfx_adc_buffer_convert(nrf_adc_value_t * buffer, uint16_t size); /** * @brief Function for retrieving the ADC state. * * @retval true If the ADC is busy. * @retval false If the ADC is ready. */ bool nrfx_adc_is_busy(void); /** * @brief Function for getting the address of the ADC START task. * * This function is used to get the address of the START task, which can be used to trigger ADC * conversion. * * @return Start task address. */ __STATIC_INLINE uint32_t nrfx_adc_start_task_get(void); #ifndef SUPPRESS_INLINE_IMPLEMENTATION __STATIC_INLINE uint32_t nrfx_adc_start_task_get(void) { return nrf_adc_task_address_get(NRF_ADC_TASK_START); } #endif void nrfx_adc_irq_handler(void); /** @} */ #ifdef __cplusplus } #endif #endif // NRFX_ADC_H__