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Diff: TARGET_SAMR21G18A/TOOLCHAIN_ARM_MICRO/adc.h
- Revision:
- 171:3a7713b1edbc
- Parent:
- 111:4336505e4b1c
diff -r e95d10626187 -r 3a7713b1edbc TARGET_SAMR21G18A/TOOLCHAIN_ARM_MICRO/adc.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/TARGET_SAMR21G18A/TOOLCHAIN_ARM_MICRO/adc.h Thu Nov 08 11:45:42 2018 +0000 @@ -0,0 +1,1140 @@ +/** + * \file + * + * \brief SAM Peripheral Analog-to-Digital Converter Driver + * + * Copyright (C) 2012-2015 Atmel Corporation. All rights reserved. + * + * \asf_license_start + * + * \page License + * + * 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. The name of Atmel may not be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * 4. This software may only be redistributed and used in connection with an + * Atmel microcontroller product. + * + * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE + * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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. + * + * \asf_license_stop + * + */ +/* + * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a> + */ + +#ifndef ADC_H_INCLUDED +#define ADC_H_INCLUDED + +/** + * \defgroup asfdoc_sam0_adc_group SAM Analog-to-Digital Converter (ADC) Driver + * + * This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration + * and management of the device's Analog-to-Digital Converter functionality, for + * the conversion of analog voltages into a corresponding digital form. + * The following driver Application Programming Interface (API) modes are covered by this manual: + * - Polled APIs + * \if ADC_CALLBACK_MODE + * - Callback APIs + * \endif + * + * The following peripheral is used by this module: + * - ADC (Analog-to-Digital Converter) + * + * The following devices can use this module: + * \if DEVICE_SAML21_SUPPORT + * - Atmel | SMART SAM L21 + * - Atmel | SMART SAM C20/C21 + * \else + * - Atmel | SMART SAM D20/D21 + * - Atmel | SMART SAM R21 + * - Atmel | SMART SAM D10/D11 + * - Atmel | SMART SAM DA0/DA1 + * \endif + * + * The outline of this documentation is as follows: + * - \ref asfdoc_sam0_adc_prerequisites + * - \ref asfdoc_sam0_adc_module_overview + * - \ref asfdoc_sam0_adc_special_considerations + * - \ref asfdoc_sam0_adc_extra_info + * - \ref asfdoc_sam0_adc_examples + * - \ref asfdoc_sam0_adc_api_overview + * + * + * \section asfdoc_sam0_adc_prerequisites Prerequisites + * + * There are no prerequisites for this module. + * + * + * \section asfdoc_sam0_adc_module_overview Module Overview + * + * This driver provides an interface for the Analog-to-Digital conversion + * functions on the device, to convert analog voltages to a corresponding + * digital value. The ADC has up to 12-bit resolution, and is capable of + * \if DEVICE_SAML21_SUPPORT + * converting up to 1,000,000 samples per second (MSPS). + * \else + * converting up to 500K samples per second (KSPS). + * \endif + * + * The ADC has a compare function for accurate monitoring of user defined + * thresholds with minimum software intervention required. + * The ADC may be configured for 8-, 10-, or 12-bit result, reducing the + * conversion time. ADC conversion results are provided left or right adjusted + * which eases calculation when the result is represented as a signed integer. + * + * The input selection is flexible, and both single-ended and differential + * measurements can be made. For differential measurements, an optional gain + * stage is available to increase the dynamic range. In addition, several + * internal signal inputs are available. The ADC can provide both signed and + * unsigned results. + * + * The ADC measurements can either be started by application software or an + * incoming event from another peripheral in the device, and both internal and + * external reference voltages can be selected. + * + * \note Internal references will be enabled by the driver, but not disabled. + * Any reference not used by the application should be disabled by the application. + * + * A simplified block diagram of the ADC can be seen in + * \ref asfdoc_sam0_adc_module_block_diagram "the figure below". + * + * \anchor asfdoc_sam0_adc_module_block_diagram + * \dot + * digraph overview { + * splines = false; + * rankdir=LR; + * + * mux1 [label="Positive input", shape=box]; + * mux2 [label="Negative input", shape=box]; + * + * + * mux3 [label="Reference", shape=box]; + * + * adc [label="ADC", shape=polygon, sides=5, orientation=90, distortion=-0.6, style=filled, fillcolor=darkolivegreen1, height=1, width=1]; + * prescaler [label="PRESCALER", shape=box, style=filled, fillcolor=lightblue]; + * + * mux1 -> adc; + * mux2 -> adc; + * mux3 -> adc:sw; + * prescaler -> adc; + * + * postproc [label="Post processing", shape=box]; + * result [label="RESULT", shape=box, style=filled, fillcolor=lightblue]; + * + * adc:e -> postproc:w; + * postproc:e -> result:w; + * + * {rank=same; mux1 mux2} + * {rank=same; prescaler adc} + * + * } + * \enddot + * + * + * \subsection asfdoc_sam0_adc_module_overview_prescaler Sample Clock Prescaler + * The ADC features a prescaler, which enables conversion at lower clock rates + * than the input Generic Clock to the ADC module. This feature can be used to + * lower the synchronization time of the digital interface to the ADC module + * via a high speed Generic Clock frequency, while still allowing the ADC + * sampling rate to be reduced. + * + * \subsection asfdoc_sam0_adc_module_overview_resolution ADC Resolution + * The ADC supports full 8-, 10-, or 12-bit resolution. Hardware + * oversampling and decimation can be used to increase the + * effective resolution at the expense of throughput. Using oversampling and + * decimation mode the ADC resolution is increased from 12-bit to an effective + * 13-, 14-, 15-, or 16-bit. In these modes the conversion rate is reduced, as + * a greater number of samples is used to achieve the increased resolution. The + * available resolutions and effective conversion rate is listed in + * \ref asfdoc_sam0_adc_module_conversion_rate "the table below". + * + * \anchor asfdoc_sam0_adc_module_conversion_rate + * <table> + * <caption>Effective ADC Conversion Speed Using Oversampling</caption> + * <tr> + * <th>Resolution</th> + * <th>Effective conversion rate</th> + * </tr> + * <tr> + * <td>13-bit</td> + * <td>Conversion rate divided by 4</td> + * </tr> + * <tr> + * <td>14-bit</td> + * <td>Conversion rate divided by 16</td> + * </tr> + * <tr> + * <td>15-bit</td> + * <td>Conversion rate divided by 64</td> + * </tr> + * <tr> + * <td>16-bit</td> + * <td>Conversion rate divided by 256</td> + * </tr> + * </table> + * + * \subsection asfdoc_sam0_adc_module_overview_conversion Conversion Modes + * ADC conversions can be software triggered on demand by the user application, + * if continuous sampling is not required. It is also possible to configure the + * ADC in free running mode, where new conversions are started as soon as the + * previous conversion is completed, or configure the ADC to scan across a + * number of input pins (see \ref asfdoc_sam0_adc_module_overview_pin_scan). + * + * \subsection asfdoc_sam0_adc_module_overview_diff_mode Differential and Single-ended Conversion + * The ADC has two conversion modes; differential and single-ended. When + * measuring signals where the positive input pin is always at a higher voltage + * than the negative input pin, the single-ended conversion mode should be used + * in order to achieve a full 12-bit output resolution. + * + * If however the positive input pin voltage may drop below the negative input + * pin the signed differential mode should be used. + * + * \subsection asfdoc_sam0_adc_module_overview_sample_time Sample Time + * The sample time for each ADC conversion is configurable as a number of half + * prescaled ADC clock cycles (depending on the prescaler value), allowing the + * user application to achieve faster or slower sampling depending on the + * source impedance of the ADC input channels. For applications with high + * impedance inputs the sample time can be increased to give the ADC an adequate + * time to sample and convert the input channel. + * + * The resulting sampling time is given by the following equation: + * \f[ + * t_{SAMPLE} = (sample\_length+1) \times \frac{ADC_{CLK}} {2} + * \f] + * + * \subsection asfdoc_sam0_adc_module_overview_averaging Averaging + * The ADC can be configured to trade conversion speed for accuracy by averaging + * multiple samples in hardware. This feature is suitable when operating in + * noisy conditions. + * + * You can specify any number of samples to accumulate (up to 1024) and the + * divide ratio to use (up to divide by 128). To modify these settings the + * ADC_RESOLUTION_CUSTOM needs to be set as the resolution. When this is set + * the number of samples to accumulate and the division ratio can be set by + * the configuration struct members \ref adc_config.accumulate_samples and + * \ref adc_config.divide_result. When using this mode the ADC result register + * will be set to be 16-bit wide to accommodate the larger result sizes + * produced by the accumulator. + * + * The effective ADC conversion rate will be reduced by a factor of the number + * of accumulated samples; + * however, the effective resolution will be increased according to + * \ref asfdoc_sam0_adc_module_hw_av_resolution "the table below". + * + * \anchor asfdoc_sam0_adc_module_hw_av_resolution + * <table> + * <caption>Effective ADC Resolution From Various Hardware Averaging Modes</caption> + * <tr> + * <th>Number of samples</tr> + * <th>Final result</tr> + * </tr> + * <tr> + * <td>1</td> + * <td>12-bit</td> + * </tr> + * <tr> + * <td>2</td> + * <td>13-bit</td> + * </tr> + * <tr> + * <td>4</td> + * <td>14-bit</td> + * </tr> + * <tr> + * <td>8</td> + * <td>15-bit</td> + * </tr> + * <tr> + * <td>16</td> + * <td>16-bit</td> + * </tr> + * <tr> + * <td>32</td> + * <td>16-bit</td> + * </tr> + * <tr> + * <td>64</td> + * <td>16-bit</td> + * </tr> + * <tr> + * <td>128</td> + * <td>16-bit</td> + * </tr> + * <tr> + * <td>256</td> + * <td>16-bit</td> + * </tr> + * <tr> + * <td>512</td> + * <td>16-bit</td> + * </tr> + * <tr> + * <td>1024</td> + * <td>16-bit</td> + * </tr> + * </table> + * + * + * \subsection asfdoc_sam0_adc_module_overview_offset_corr Offset and Gain Correction + * Inherent gain and offset errors affect the absolute accuracy of the ADC. + * + * The offset error is defined as the deviation of the ADC's actual transfer + * function from ideal straight line at zero input voltage. + * + * The gain error is defined as the deviation of the last output step's + * midpoint from the ideal straight line, after compensating for offset error. + * + * The offset correction value is subtracted from the converted data before the + * result is ready. The gain correction value is multiplied with the offset + * corrected value. + * + * The equation for both offset and gain error compensation is shown below: + * \f[ + * ADC_{RESULT} = (VALUE_{CONV} + CORR_{OFFSET}) \times CORR_{GAIN} + * \f] + * + * When enabled, a given set of offset and gain correction values can be applied + * to the sampled data in hardware, giving a corrected stream of sample data to + * the user application at the cost of an increased sample latency. + * + * In single conversion, a latency of 13 ADC Generic Clock cycles is added for + * the final sample result availability. As the correction time is always less + * than the propagation delay, in free running mode this latency appears only + * during the first conversion. After the first conversion is complete, future + * conversion results are available at the defined sampling rate. + * + * \subsection asfdoc_sam0_adc_module_overview_pin_scan Pin Scan + * In pin scan mode, the first ADC conversion will begin from the configured + * positive channel, plus the requested starting offset. When the first + * conversion is completed, the next conversion will start at the next positive + * input channel and so on, until all requested pins to scan have been sampled + * and converted. + * SAM L21 has automatic sequences feature instead of pin scan mode. In automatic + * sequence mode, all of 32 positives inputs can be included in a sequence. The + * sequence starts from the lowest input, and go to the next enabled input + * automatically. + * + * Pin scanning gives a simple mechanism to sample a large number of physical + * input channel samples, using a single physical ADC channel. + * + * \subsection asfdoc_sam0_adc_module_overview_window_monitor Window Monitor + * The ADC module window monitor function can be used to automatically compare + * the conversion result against a preconfigured pair of upper and lower + * threshold values. + * + * The threshold values are evaluated differently, depending on whether + * differential or single-ended mode is selected. In differential mode, the + * upper and lower thresholds are evaluated as signed values for the comparison, + * while in single-ended mode the comparisons are made as a set of unsigned + * values. + * + * The significant bits of the lower window monitor threshold and upper window + * monitor threshold values are user-configurable, and follow the overall ADC + * sampling bit precision set when the ADC is configured by the user application. + * For example, only the eight lower bits of the window threshold values will be + * compared to the sampled data whilst the ADC is configured in 8-bit mode. + * In addition, if using differential mode, the 8<SUP>th</SUP> bit will be considered as + * the sign bit even if bit 9 is zero. + * + * \subsection asfdoc_sam0_adc_module_overview_events Events + * Event generation and event actions are configurable in the ADC. + * + * The ADC has two actions that can be triggered upon event reception: + * \li Start conversion + * \li Flush pipeline and start conversion + * + * The ADC can generate two events: + * \li Window monitor + * \li Result ready + * + * If the event actions are enabled in the configuration, any incoming event + * will trigger the action. + * + * If the window monitor event is enabled, an event will be generated + * when the configured window condition is detected. + * + * If the result ready event is enabled, an event will be generated when a + * conversion is completed. + * + * \note The connection of events between modules requires the use of the + * \ref asfdoc_sam0_events_group "SAM Event System Driver (EVENTS)" + * to route output event of one module to the the input event of another. + * For more information on event routing, refer to the event driver + * documentation. + * + * + * \section asfdoc_sam0_adc_special_considerations Special Considerations + * + * An integrated analog temperature sensor is available for use with the ADC. + * The bandgap voltage, as well as the scaled I/O and core voltages can also be + * measured by the ADC. For internal ADC inputs, the internal source(s) may need + * to be manually enabled by the user application before they can be measured. + * + * + * \section asfdoc_sam0_adc_extra_info Extra Information + * + * For extra information, see \ref asfdoc_sam0_adc_extra. This includes: + * - \ref asfdoc_sam0_adc_extra_acronyms + * - \ref asfdoc_sam0_adc_extra_dependencies + * - \ref asfdoc_sam0_adc_extra_errata + * - \ref asfdoc_sam0_adc_extra_history + * + * + * \section asfdoc_sam0_adc_examples Examples + * + * For a list of examples related to this driver, see + * \ref asfdoc_sam0_adc_exqsg. + * + * + * \section asfdoc_sam0_adc_api_overview API Overview + * @{ + */ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <compiler.h> +#include <system.h> +#include <adc_feature.h> + +/** + * \name Module Status Flags + * + * ADC status flags, returned by \ref adc_get_status() and cleared by + * \ref adc_clear_status(). + * + * @{ + */ + +/** ADC result ready. */ +#define ADC_STATUS_RESULT_READY (1UL << 0) +/** Window monitor match. */ +#define ADC_STATUS_WINDOW (1UL << 1) +/** ADC result overwritten before read. */ +#define ADC_STATUS_OVERRUN (1UL << 2) + +/** @} */ + +#if ADC_CALLBACK_MODE == true +# if (ADC_INST_NUM > 1) +# define _ADC_INTERRUPT_VECT_NUM(n, unused) \ + SYSTEM_INTERRUPT_MODULE_ADC##n, +/** + * \internal Get the interrupt vector for the given device instance + * + * \param[in] The ADC module instance number + * + * \return Interrupt vector for of the given ADC module instance. + */ +static enum system_interrupt_vector _adc_interrupt_get_interrupt_vector( + uint32_t inst_num) +{ + static uint8_t adc_interrupt_vectors[ADC_INST_NUM] = { + MREPEAT(ADC_INST_NUM, _ADC_INTERRUPT_VECT_NUM, 0) + }; + + return (enum system_interrupt_vector)adc_interrupt_vectors[inst_num]; +} +# endif +#endif + +#if !defined(__DOXYGEN__) +uint8_t _adc_get_inst_index( + Adc *const hw); +#endif + +/** + * \name Driver Initialization and Configuration + * @{ + */ +enum status_code adc_init( + struct adc_module *const module_inst, + Adc *hw, + struct adc_config *config); + +void adc_get_config_defaults( + struct adc_config *const config); + +#if (SAMD) || (SAMR21) +void adc_regular_ain_channel( + uint32_t *pin_array, uint8_t size); +#endif + +/** @} */ + +/** + * \name Status Management + * @{ + */ + +/** + * \brief Retrieves the current module status. + * + * Retrieves the status of the module, giving overall state information. + * + * \param[in] module_inst Pointer to the ADC software instance struct + * + * \return Bitmask of \c ADC_STATUS_* flags. + * + * \retval ADC_STATUS_RESULT_READY ADC result is ready to be read + * \retval ADC_STATUS_WINDOW ADC has detected a value inside the set + * window range + * \retval ADC_STATUS_OVERRUN ADC result has overrun + */ +static inline uint32_t adc_get_status( + struct adc_module *const module_inst) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + + uint32_t int_flags = adc_module->INTFLAG.reg; + + uint32_t status_flags = 0; + + /* Check for ADC Result Ready */ + if (int_flags & ADC_INTFLAG_RESRDY) { + status_flags |= ADC_STATUS_RESULT_READY; + } + + /* Check for ADC Window Match */ + if (int_flags & ADC_INTFLAG_WINMON) { + status_flags |= ADC_STATUS_WINDOW; + } + + /* Check for ADC Overrun */ + if (int_flags & ADC_INTFLAG_OVERRUN) { + status_flags |= ADC_STATUS_OVERRUN; + } + + return status_flags; +} + +/** + * \brief Clears a module status flag. + * + * Clears the given status flag of the module. + * + * \param[in] module_inst Pointer to the ADC software instance struct + * \param[in] status_flags Bitmask of \c ADC_STATUS_* flags to clear + */ +static inline void adc_clear_status( + struct adc_module *const module_inst, + const uint32_t status_flags) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + + uint32_t int_flags = 0; + + /* Check for ADC Result Ready */ + if (status_flags & ADC_STATUS_RESULT_READY) { + int_flags |= ADC_INTFLAG_RESRDY; + } + + /* Check for ADC Window Match */ + if (status_flags & ADC_STATUS_WINDOW) { + int_flags |= ADC_INTFLAG_WINMON; + } + + /* Check for ADC Overrun */ + if (status_flags & ADC_STATUS_OVERRUN) { + int_flags |= ADC_INTFLAG_OVERRUN; + } + + /* Clear interrupt flag */ + adc_module->INTFLAG.reg = int_flags; +} +/** @} */ + +/** + * \name Enable, Disable, and Reset ADC Module, Start Conversion and Read Result + * @{ + */ + +/** + * \brief Enables the ADC module. + * + * Enables an ADC module that has previously been configured. If any internal reference + * is selected it will be enabled. + * + * \param[in] module_inst Pointer to the ADC software instance struct + */ +static inline enum status_code adc_enable( + struct adc_module *const module_inst) +{ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } + +#if ADC_CALLBACK_MODE == true +# if (ADC_INST_NUM > 1) + system_interrupt_enable(_adc_interrupt_get_interrupt_vector( + _adc_get_inst_index(adc_module))); +# elif (SAMC20) + system_interrupt_enable(SYSTEM_INTERRUPT_MODULE_ADC0); +# else + system_interrupt_enable(SYSTEM_INTERRUPT_MODULE_ADC); +# endif +#endif + + adc_module->CTRLA.reg |= ADC_CTRLA_ENABLE; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } + return STATUS_OK; +} + +/** + * \brief Disables the ADC module. + * + * Disables an ADC module that was previously enabled. + * + * \param[in] module_inst Pointer to the ADC software instance struct + */ +static inline enum status_code adc_disable( + struct adc_module *const module_inst) +{ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + +#if ADC_CALLBACK_MODE == true +# if (ADC_INST_NUM > 1) + system_interrupt_disable(_adc_interrupt_get_interrupt_vector( + _adc_get_inst_index(adc_module))); +# elif (SAMC20) + system_interrupt_disable(SYSTEM_INTERRUPT_MODULE_ADC0); +# else + system_interrupt_disable(SYSTEM_INTERRUPT_MODULE_ADC); +# endif +#endif + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } + + adc_module->CTRLA.reg &= ~ADC_CTRLA_ENABLE; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } + return STATUS_OK; +} + +/** + * \brief Resets the ADC module. + * + * Resets an ADC module, clearing all module state and registers to their + * default values. + * + * \param[in] module_inst Pointer to the ADC software instance struct + */ +static inline enum status_code adc_reset( + struct adc_module *const module_inst) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + + /* Disable to make sure the pipeline is flushed before reset */ + adc_disable(module_inst); + + /* Software reset the module */ + adc_module->CTRLA.reg |= ADC_CTRLA_SWRST; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } + return STATUS_OK; +} + + +/** + * \brief Enables an ADC event input or output. + * + * Enables one or more input or output events to or from the ADC module. See + * \ref adc_events "Struct adc_events" for a list of events this module supports. + * + * \note Events cannot be altered while the module is enabled. + * + * \param[in] module_inst Software instance for the ADC peripheral + * \param[in] events Struct containing flags of events to enable + */ +static inline void adc_enable_events( + struct adc_module *const module_inst, + struct adc_events *const events) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + Assert(events); + + Adc *const adc_module = module_inst->hw; + + uint32_t event_mask = 0; + + /* Configure Window Monitor event */ + if (events->generate_event_on_window_monitor) { + event_mask |= ADC_EVCTRL_WINMONEO; + } + + /* Configure Result Ready event */ + if (events->generate_event_on_conversion_done) { + event_mask |= ADC_EVCTRL_RESRDYEO; + } + + adc_module->EVCTRL.reg |= event_mask; +} + +/** + * \brief Disables an ADC event input or output. + * + * Disables one or more input or output events to or from the ADC module. See + * \ref adc_events "Struct adc_events" for a list of events this module supports. + * + * \note Events cannot be altered while the module is enabled. + * + * \param[in] module_inst Software instance for the ADC peripheral + * \param[in] events Struct containing flags of events to disable + */ +static inline void adc_disable_events( + struct adc_module *const module_inst, + struct adc_events *const events) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + Assert(events); + + Adc *const adc_module = module_inst->hw; + + uint32_t event_mask = 0; + + /* Configure Window Monitor event */ + if (events->generate_event_on_window_monitor) { + event_mask |= ADC_EVCTRL_WINMONEO; + } + + /* Configure Result Ready event */ + if (events->generate_event_on_conversion_done) { + event_mask |= ADC_EVCTRL_RESRDYEO; + } + + adc_module->EVCTRL.reg &= ~event_mask; +} + +/** + * \brief Starts an ADC conversion. + * + * Starts a new ADC conversion. + * + * \param[in] module_inst Pointer to the ADC software instance struct + */ +static inline void adc_start_conversion( + struct adc_module *const module_inst) +{ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } + + adc_module->SWTRIG.reg |= ADC_SWTRIG_START; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } +} + +/** + * \brief Reads the ADC result. + * + * Reads the result from an ADC conversion that was previously started. + * + * \param[in] module_inst Pointer to the ADC software instance struct + * \param[out] result Pointer to store the result value in + * + * \return Status of the ADC read request. + * \retval STATUS_OK The result was retrieved successfully + * \retval STATUS_BUSY A conversion result was not ready + * \retval STATUS_ERR_OVERFLOW The result register has been overwritten by the + * ADC module before the result was read by the software + */ +static inline enum status_code adc_read( + struct adc_module *const module_inst, + uint16_t *result) +{ + Assert(module_inst); + Assert(module_inst->hw); + Assert(result); + + if (!(adc_get_status(module_inst) & ADC_STATUS_RESULT_READY)) { + /* Result not ready */ + return STATUS_BUSY; + } + + Adc *const adc_module = module_inst->hw; + +#if (SAMD) || (SAMR21) + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } +#endif + + /* Get ADC result */ + *result = adc_module->RESULT.reg; + + /* Reset ready flag */ + adc_clear_status(module_inst, ADC_STATUS_RESULT_READY); + + if (adc_get_status(module_inst) & ADC_STATUS_OVERRUN) { + adc_clear_status(module_inst, ADC_STATUS_OVERRUN); + return STATUS_ERR_OVERFLOW; + } + + return STATUS_OK; +} + +/** @} */ + +/** + * \name Runtime Changes of ADC Module + * @{ + */ + +/** + * \brief Flushes the ADC pipeline. + * + * Flushes the pipeline and restarts the ADC clock on the next peripheral clock + * edge. All conversions in progress will be lost. When flush is complete, the + * module will resume where it left off. + * + * \param[in] module_inst Pointer to the ADC software instance struct + */ +static inline void adc_flush( + struct adc_module *const module_inst) +{ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } + + adc_module->SWTRIG.reg |= ADC_SWTRIG_FLUSH; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } +} +void adc_set_window_mode( + struct adc_module *const module_inst, + const enum adc_window_mode window_mode, + const int16_t window_lower_value, + const int16_t window_upper_value); + +/** + * \brief Sets positive ADC input pin. + * + * Sets the positive ADC input pin selection. + * + * \param[in] module_inst Pointer to the ADC software instance struct + * \param[in] positive_input Positive input pin + */ +static inline void adc_set_positive_input( + struct adc_module *const module_inst, + const enum adc_positive_input positive_input) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } + + /* Set positive input pin */ + adc_module->INPUTCTRL.reg = + (adc_module->INPUTCTRL.reg & ~ADC_INPUTCTRL_MUXPOS_Msk) | + (positive_input); + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } +} + + +/** + * \brief Sets negative ADC input pin for differential mode. + * + * Sets the negative ADC input pin, when the ADC is configured in differential + * mode. + * + * \param[in] module_inst Pointer to the ADC software instance struct + * \param[in] negative_input Negative input pin + */ +static inline void adc_set_negative_input( + struct adc_module *const module_inst, + const enum adc_negative_input negative_input) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } + + /* Set negative input pin */ + adc_module->INPUTCTRL.reg = + (adc_module->INPUTCTRL.reg & ~ADC_INPUTCTRL_MUXNEG_Msk) | + (negative_input); + + while (adc_is_syncing(module_inst)) { + /* Wait for synchronization */ + } +} + +/** @} */ + +#if ADC_CALLBACK_MODE == true +/** + * \name Enable and Disable Interrupts + * @{ + */ + +/** + * \brief Enable interrupt. + * + * Enable the given interrupt request from the ADC module. + * + * \param[in] module_inst Pointer to the ADC software instance struct + * \param[in] interrupt Interrupt to enable + */ +static inline void adc_enable_interrupt(struct adc_module *const module_inst, + enum adc_interrupt_flag interrupt) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + /* Enable interrupt */ + adc_module->INTENSET.reg = interrupt; +} + +/** + * \brief Disable interrupt. + * + * Disable the given interrupt request from the ADC module. + * + * \param[in] module_inst Pointer to the ADC software instance struct + * \param[in] interrupt Interrupt to disable + */ +static inline void adc_disable_interrupt(struct adc_module *const module_inst, + enum adc_interrupt_flag interrupt) +{ + /* Sanity check arguments */ + Assert(module_inst); + Assert(module_inst->hw); + + Adc *const adc_module = module_inst->hw; + /* Enable interrupt */ + adc_module->INTENCLR.reg = interrupt; +} + +/** @} */ +#endif /* ADC_CALLBACK_MODE == true */ + +#ifdef __cplusplus +} +#endif + +/** @} */ + + +/** + * \page asfdoc_sam0_adc_extra Extra Information for ADC Driver + * + * \section asfdoc_sam0_adc_extra_acronyms Acronyms + * Below is a table listing the acronyms used in this module, along with their + * intended meanings. + * + * <table> + * <tr> + * <th>Acronym</th> + * <th>Description</th> + * </tr> + * <tr> + * <td>ADC</td> + * <td>Analog-to-Digital Converter</td> + * </tr> + * <tr> + * <td>DAC</td> + * <td>Digital-to-Analog Converter</td> + * </tr> + * <tr> + * <td>LSB</td> + * <td>Least Significant Bit</td> + * </tr> + * <tr> + * <td>MSB</td> + * <td>Most Significant Bit</td> + * </tr> + * <tr> + * <td>DMA</td> + * <td>Direct Memory Access</td> + * </tr> + * </table> + * + * + * \section asfdoc_sam0_adc_extra_dependencies Dependencies + * This driver has the following dependencies: + * + * - \ref asfdoc_sam0_system_pinmux_group "System Pin Multiplexer Driver" + * + * + * \section asfdoc_sam0_adc_extra_errata Errata + * There are no errata related to this driver. + * + * + * \section asfdoc_sam0_adc_extra_history Module History + * An overview of the module history is presented in the table below, with + * details on the enhancements and fixes made to the module since its first + * release. The current version of this corresponds to the newest version in + * the table. + * + * <table> + * <tr> + * <th>Changelog</th> + * </tr> + * \if DEVICE_SAML21_SUPPORT + * <tr> + * <td>Initial Release</td> + * </tr> + * \else + * <tr> + * <td>Added support for SAMR21</td> + * </tr> + * <tr> + * <td>Added support for SAMD21 and new DMA quick start guide</td> + * </tr> + * <tr> + * <td>Added ADC calibration constant loading from the device signature + * row when the module is initialized</td> + * </tr> + * <tr> + * <td>Initial Release</td> + * </tr> + * \endif + * </table> + */ + +/** + * \page asfdoc_sam0_adc_exqsg Examples for ADC Driver + * + * This is a list of the available Quick Start guides (QSGs) and example + * applications for \ref asfdoc_sam0_adc_group. QSGs are simple examples with + * step-by-step instructions to configure and use this driver in a selection of + * use cases. Note that a QSG can be compiled as a standalone application or be + * added to the user application. + * + * - \subpage asfdoc_sam0_adc_basic_use_case + * \if ADC_CALLBACK_MODE + * - \subpage asfdoc_sam0_adc_basic_use_case_callback + * \endif + * - \subpage asfdoc_sam0_adc_dma_use_case + * + * \page asfdoc_sam0_adc_document_revision_history Document Revision History + * + * <table> + * <tr> + * <th>Doc. Rev.</td> + * <th>Date</td> + * <th>Comments</td> + * </tr> + * \if DEVICE_SAML21_SUPPORT + * <tr> + * <td>42451A</td> + * <td>07/2015</td> + * <td>Initial document release</td> + * </tr> + * \else + * <tr> + * <td>42109E</td> + * <td>04/2015</td> + * <td>Added support for SAMDAx.</td> + * </tr> + * <tr> + * <td>42109D</td> + * <td>12/2014</td> + * <td>Added support for SAMR21 and SAMD10/D11</td> + * </tr> + * <tr> + * <td>42109C</td> + * <td>01/2014</td> + * <td>Added support for SAMD21</td> + * </tr> + * <tr> + * <td>42109B</td> + * <td>06/2013</td> + * <td>Added additional documentation on the event system. Corrected + * documentation typos.</td> + * </tr> + * <tr> + * <td>42109A</td> + * <td>06/2013</td> + * <td>Initial release</td> + * </tr> + * \endif + * </table> + */ + +#endif /* ADC_H_INCLUDED */