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Diff: targets/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/dac/TARGET_SAML21/dac_feature.h
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diff -r 21d94c44109e -r 156823d33999 targets/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/dac/TARGET_SAML21/dac_feature.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_Atmel/TARGET_SAM_CortexM0P/drivers/dac/TARGET_SAML21/dac_feature.h Fri Oct 28 11:17:30 2016 +0100 @@ -0,0 +1,611 @@ +/** + * \file + * + * \brief SAM Peripheral Digital-to-Analog Converter Driver + * + * Copyright (C) 2014-2015 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 DAC_FEATURE_H_INCLUDED +#define DAC_FEATURE_H_INCLUDED + +/** + * \defgroup asfdoc_sam0_dac_group SAM Digital-to-Analog (DAC) Driver + * + * This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the conversion of + * digital values to analog voltage. The following driver API modes are covered + * by this manual: + * + * - Polled APIs + * \if DAC_CALLBACK_MODE + * - Callback APIs + * \endif + * + * The following peripheral is used by this module: + * - DAC (Digital-to-Analog Converter) + * + * The following devices can use this module: + * - Atmel | SMART SAM L21 + * + * The outline of this documentation is as follows: + * - \ref asfdoc_sam0_dac_prerequisites + * - \ref asfdoc_sam0_dac_module_overview + * - \ref asfdoc_sam0_dac_special_considerations + * - \ref asfdoc_sam0_dac_extra_info + * - \ref asfdoc_sam0_dac_examples + * - \ref asfdoc_sam0_dac_api_overview + * + * + * \section asfdoc_sam0_dac_prerequisites Prerequisites + * + * There are no prerequisites for this module. + * + * + * \section asfdoc_sam0_dac_module_overview Module Overview + * + * The Digital-to-Analog converter converts a digital value to an analog voltage. + * The DAC Controller can operate as two independent DACs or as a single DAC + * in differential mode. Each DAC has a 12-bit resolution and it is capable of + * converting up to 1M samples per second (Msps). + * + * A common use of DAC is to generate audio signals by connecting the DAC + * output to a speaker, or to generate a reference voltage; either for an + * external circuit or an internal peripheral such as the Analog Comparator. + * + * After being set up, the DAC will convert new digital values written to the + * conversion data register (DATA0 or DATA1) to an analog value either on the + * DAC output (VOUT0 or VOUT1) pin of the device, or internally for use as an + * input to the AC, ADC, and other analog modules. + * + * Writing the DATA register will start a new conversion. It is also possible + * to trigger the conversion from the event system. + * + * A simplified block diagram of the DAC can be seen in + * \ref asfdoc_sam0_dac_module_block_diagram "the figure below". + * + * \anchor asfdoc_sam0_dac_module_block_diagram + * \image html dac_block_diagram_saml.svg "DAC Block Diagram" + * + * \subsection asfdoc_sam0_dac_conversion_range Conversion Range + * The conversion range is between GND and the selected voltage reference. + * Available voltage references are: + * \li Voltage supply (VDDANA) + * \li Internal bandgap reference (INTREF) + * \li Unbuffered External voltage reference (VREFPU) + * \li Buffered External voltage reference (VREFPB) + * + * \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. + * + * The output voltage from a DAC channel is given as: + * \f[ + * V_{OUTx} = \frac{DATAx}{0x3FF} \times VREF + * \f] + * The differential output voltage is given as: + * \f[ + * V_{OUT} = \frac{DATA0}{0x1FF} \times VREF = (V_{OUT0}-V_{OUT1}) + * \f] + * + * \subsection asfdoc_sam0_dac_conversion Conversion + * The conversion digital value written to the DATA register will be converted + * to an analog value. Writing the DATA register will start a new conversion. + * It is also possible to write the conversion value to the DATABUF register, + * the writing of the DATA register can then be triggered from the event + * system, which will load the value from DATABUF to DATA. + * + * \subsection asfdoc_sam0_dac_analog_output Analog Output + * The analog output value can be output to the VOUTx converted by DACx, and + * each data conversion can be started independently. + * + * In differential mode, DAC0 and DAC1 are operating synchronously to convert + * value. VOUT0 is the positive output and VOUT1 the negative output. + * + * VOUT0 signal is internally connected so that it can be used as input for + * AC, ADC, or OPAMP modules when DAC0 is enabled. + * \note The pin VOUT0 will be dedicated to internal input and cannot be + * configured as alternate function. + * + * \subsection asfdoc_sam0_dac_events Events + * Events generation and event actions are configurable in the DAC. + * The DAC has one event line input and one event output: <i>Start Conversion</i> + * and <i>Data Buffer Empty</i>. + * + * If the Start Conversion input event is enabled in the module configuration, + * an incoming event will load data from the data buffer to the data register + * and start a new conversion. This method synchronizes conversions with + * external events (such as those from a timer module) and ensures regular and + * fixed conversion intervals. + * + * If the Data Buffer Empty output event is enabled in the module configuration, + * events will be generated when the DAC data buffer register becomes empty and + * new data can be loaded to the buffer. + * + * \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. + * + * \subsection asfdoc_sam0_dac_data_adjust Left and Right Adjusted Values + * The 12-bit input value to the DAC is contained in a 16-bit register. This + * can be configured to be either left or right adjusted. In + * \ref asfdoc_sam0_dac_module_adj_modes "the figure below" both options are + * shown, and the position of the most (MSB) and the least (LSB) significant bits + * are indicated. The unused bits should always be written to zero. + * + * \anchor asfdoc_sam0_dac_module_adj_modes + * \dot + * digraph { + * subgraph cluster_right { + * msbl [label="MSB", shape=none, group="msbl"]; + * lsbl [label="LSB", shape=none]; + * node [shape=none]; + * color="white"; + * reg_left [label=< + * <table cellspacing="0" cellpadding="2" width="100%"> + * <tr> + * <td port="msb">15</td> + * <td>14</td> + * <td>13</td> + * <td>12</td> + * <td>11</td> + * <td>10</td> + * <td>9</td> + * <td>8</td> + * <td>7</td> + * <td>6</td> + * <td>5</td> + * <td port="lsb">4</td> + * <td>3</td> + * <td>2</td> + * <td>1</td> + * <td>0</td> + * </tr> + * <tr> + * <td COLSPAN="12"> DATA[11:0] </td> + * <td BGCOLOR="lightgray"> </td> + * <td BGCOLOR="lightgray"> </td> + * <td BGCOLOR="lightgray"> </td> + * <td BGCOLOR="lightgray"> </td> + * </tr> + * </table> + * >]; + * msbl -> reg_left:msb:n; + * lsbl -> reg_left:lsb; + * label ="Left adjusted.\n"; + * } + * subgraph cluster_left { + * rankdir=TB; + * msb [label="MSB", shape=none]; + * lsb [label="LSB", shape=none]; + * color="white"; + * node [shape=none]; + * reg_right [label=< + * <table cellspacing="0" cellpadding="2"> + * <tr> + * <td>15</td> + * <td>14</td> + * <td>13</td> + * <td>12</td> + * <td port="msb">11</td> + * <td>10</td> + * <td>9</td> + * <td>8</td> + * <td>7</td> + * <td>6</td> + * <td>5</td> + * <td>4</td> + * <td>3</td> + * <td>2</td> + * <td>1</td> + * <td port="lsb">0</td> + * </tr> + * <tr> + * <td BGCOLOR="lightgray"></td> + * <td BGCOLOR="lightgray"></td> + * <td BGCOLOR="lightgray"></td> + * <td BGCOLOR="lightgray"></td> + * <td COLSPAN="12"> DATA[11:0] </td> + * </tr> + * </table> + * >]; + * msb -> reg_right:msb; + * lsb -> reg_right:lsb:n; + * label = "Right adjusted.\n"; + * graph [shape=none]; + * } + * } + * \enddot + * + * \subsection asfdoc_sam0_dac_clk_sources Clock Sources + * The clock for the DAC interface (CLK_DAC) is generated by the Power Manager. + * This clock is turned on by default, and can be enabled and disabled in the + * Power Manager. + * + * Additionally, an asynchronous clock source (GCLK_DAC) is required. + * These clocks are normally disabled by default. The selected clock source + * must be enabled in the Power Manager before it can be used by the DAC. + * The DAC core operates asynchronously from the user interface and + * peripheral bus. As a consequence, the DAC needs two clock cycles of both + * CLK_DAC and GCLK_DAC to synchronize the values written to some of the + * control and data registers. + * The oscillator source for the GCLK_DAC clock is selected in the Supply + * Control Interface (SUPC). + * + * \section asfdoc_sam0_dac_special_considerations Special Considerations + * + * \subsection asfdoc_sam0_dac_special_considerations_sleep Sleep Mode + * The DAC can do conversions in Active or Idle modes, and will continue the + * conversions in standby sleep mode if the RUNSTDBY bit in the DACCTRLx + * register is set. Otherwise, the DACx will stop conversions. + * + * If DACx conversion is stopped in standby sleep mode, DACx is disabled to + * reduce power consumption. When exiting standby sleep mode, DACx is enabled + * therefore startup time is required before starting a new conversion. + * + * \subsection asfdoc_sam0_dac_special_considerations_conversion_time Conversion Time + * DAC conversion time is approximately 2.85µs. The user must ensure that new + * data is not written to the DAC before the last conversion is complete. + * Conversions should be triggered by a periodic event from a Timer/Counter or + * another peripheral. + * + * + * \section asfdoc_sam0_dac_extra_info Extra Information + * + * For extra information, see \ref asfdoc_sam0_dac_extra. This includes: + * - \ref asfdoc_sam0_dac_extra_acronyms + * - \ref asfdoc_sam0_dac_extra_dependencies + * - \ref asfdoc_sam0_dac_extra_errata + * - \ref asfdoc_sam0_dac_extra_history + * + * + * \section asfdoc_sam0_dac_examples Examples + * + * For a list of examples related to this driver, see + * \ref asfdoc_sam0_dac_exqsg. + * + * + * \section asfdoc_sam0_dac_api_overview API Overview + * @{ + */ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <compiler.h> +#include <clock.h> +#include <gclk.h> + + +/** + * \name DAC Status Flags + * + * DAC status flags, returned by \ref dac_get_status() and cleared by + * \ref dac_clear_status(). + * @{ + */ + +/** Data Buffer Empty Channel 0 - Set when data is transferred from DATABUF + * to DATA by a start conversion event and DATABUF is ready for new data. + */ +#define DAC_STATUS_CHANNEL_0_EMPTY (1UL << 0) + +/** Data Buffer Empty Channel 1 - Set when data is transferred from DATABUF + * to DATA by a start conversion event and DATABUF is ready for new data. + */ +#define DAC_STATUS_CHANNEL_1_EMPTY (1UL << 1) + +/** Underrun Channel 0 - Set when a start conversion event occurs when + * DATABUF is empty. + */ +#define DAC_STATUS_CHANNEL_0_UNDERRUN (1UL << 2) + +/** Underrun Channel 1 - Set when a start conversion event occurs when + * DATABUF is empty. + */ +#define DAC_STATUS_CHANNEL_1_UNDERRUN (1UL << 3) + +/** @} */ + +/** + * \brief DAC reference voltage enum. + * + * Enum for the possible reference voltages for the DAC. + */ +enum dac_reference { + /** Unbuffered external voltage reference */ + DAC_REFERENCE_VREFPU = DAC_CTRLB_REFSEL(0), + /** Analog VCC as reference */ + DAC_REFERENCE_VDDANA = DAC_CTRLB_REFSEL(1), + /** Buffered external voltage reference */ + DAC_REFERENCE_VREFPB = DAC_CTRLB_REFSEL(2), + /** Internal bandgap reference */ + DAC_REFERENCE_INTREF = DAC_CTRLB_REFSEL(3), +}; + +/** + * \brief DAC current control enum. + * + * Enum for the current in output buffer according the conversion rate. + */ +enum dac_current_ctrl { + /** 1MHz < GCLK_DAC < 12MHz */ + DAC_CURRENT_12M = DAC_DACCTRL_CCTRL(0), + /** 100KHz < GCLK_DAC < 1MHz */ + DAC_CURRENT_1M = DAC_DACCTRL_CCTRL(1), + /** 10KHz < GCLK_DAC < 100KHz */ + DAC_CURRENT_100K = DAC_DACCTRL_CCTRL(2), + /** GCLK_DAC < 10KHz */ + DAC_CURRENT_10K = DAC_DACCTRL_CCTRL(3), +}; + +/** + * \brief DAC channel selection enum. + * + * Enum for the DAC channel selection. + */ +enum dac_channel { + /** DAC output channel 0 */ + DAC_CHANNEL_0, + /** DAC output channel 1 */ + DAC_CHANNEL_1, +#if !defined(__DOXYGEN__) + DAC_CHANNEL_N, +#endif +}; + +/** + * \brief DAC software device instance structure. + * + * DAC software instance structure, used to retain software state information + * of an associated hardware module instance. + * + * \note The fields of this structure should not be altered by the user + * application; they are reserved for module-internal use only. + */ +struct dac_module { +#if !defined(__DOXYGEN__) + /** DAC hardware module */ + Dac *hw; + /** Reference selection */ + enum dac_reference reference; + /** DAC event selection */ + bool start_on_event[DAC_CHANNEL_N]; +# if DAC_CALLBACK_MODE == true + /** Pointer to buffer used for ADC results */ + volatile uint16_t *job_buffer[DAC_CHANNEL_N]; + /** Remaining number of conversions in current job */ + volatile uint16_t remaining_conversions[DAC_CHANNEL_N]; + /** Transferred number of conversions in current job */ + volatile uint16_t transferred_conversions[DAC_CHANNEL_N]; + /** DAC callback enable */ + bool callback_enable[DAC_CHANNEL_N][DAC_CALLBACK_N]; + /** DAC registered callback functions */ + dac_callback_t callback[DAC_CHANNEL_N][DAC_CALLBACK_N]; + /** Holds the status of the ongoing or last conversion job */ + volatile enum status_code job_status[DAC_CHANNEL_N]; +# endif +#endif +}; + +/** + * \brief DAC configuration structure. + * + * Configuration structure for a DAC instance. This structure should be + * initialized by the \ref dac_get_config_defaults() + * function before being modified by the user application. + */ +struct dac_config { + /** Differential mode enable data */ + bool differential_mode; + /** Reference voltage */ + enum dac_reference reference; + /** GCLK generator used to clock the peripheral */ + enum gclk_generator clock_source; +}; + +/** + * \brief DAC channel configuration structure. + * + * Configuration for a DAC channel. This structure should be initialized by the + * \ref dac_chan_get_config_defaults() function before being modified by the + * user application. + */ +struct dac_chan_config { + /** Left adjusted data */ + bool left_adjust; + /** Current control data */ + enum dac_current_ctrl current; + /** + * The DAC behaves as in normal mode when the chip enters STANDBY sleep + * mode + */ + bool run_in_standby; + /** Dither mode enable data */ + bool dither_mode; + /** + * The DAC conversion refreshed periodically when used to generate a static + * voltage + */ + uint8_t refresh_period; +}; + +/** + * \brief DAC event enable/disable structure. + * + * Event flags for the DAC module. This is used to enable and + * disable events via \ref dac_enable_events() and \ref dac_disable_events(). + */ +struct dac_events { + /** Start a new DAC0 conversion */ + bool on_event_chan0_start_conversion; + /** Start a new DAC1 conversion */ + bool on_event_chan1_start_conversion; + /** Enable event generation on DAC0 data buffer empty */ + bool generate_event_on_chan0_buffer_empty; + /** Enable event generation on DAC1 data buffer empty */ + bool generate_event_on_chan1_buffer_empty; + /** Enable the falling edge of the input event for DAC0 */ + bool generate_event_on_chan0_falling_edge; + /** Enable the falling edge of the input event for DAC1 */ + bool generate_event_on_chan1_falling_edge; +}; + +/** + * \name Status Management (Channel) + * @{ + */ +bool dac_chan_is_end_of_conversion( + struct dac_module *const module_inst, + enum dac_channel channel); +/** @} */ + +/** @} */ + +/** + * \page asfdoc_sam0_dac_extra Extra Information for DAC Driver + * + * \section asfdoc_sam0_dac_extra_acronyms Acronyms + * The table below presents the acronyms used in this module: + * + * <table> + * <tr> + * <th>Acronym</th> + * <th>Description</th> + * </tr> + * <tr> + * <td>ADC</td> + * <td>Analog-to-Digital Converter</td> + * </tr> + * <tr> + * <td>AC</td> + * <td>Analog Comparator</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_dac_extra_dependencies Dependencies + * This driver has the following dependency: + * + * - \ref asfdoc_sam0_system_pinmux_group "System Pin Multiplexer Driver" + * + * + * \section asfdoc_sam0_dac_extra_errata Errata + * There are no errata related to this driver. + * + * + * \section asfdoc_sam0_dac_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> + * <tr> + * <td>Initial Release</td> + * </tr> + * </table> + */ + +/** + * \page asfdoc_sam0_dac_exqsg Examples for DAC Driver + * + * This is a list of the available Quick Start guides (QSGs) and example + * applications for \ref asfdoc_sam0_dac_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_dac_basic_use_case + * \if DAC_CALLBACK_MODE + * - \subpage asfdoc_sam0_dac_basic_use_case_callback + * \endif + * \if DAC_DMA_USE_MODE_SELECTION + * - \subpage asfdoc_sam0_adc_dma_use_case_dac_in_dma + * \endif + * + * \if DAC_DMA_USE_MODE_SELECTION + * \page asfdoc_sam0_adc_dma_use_case_dac_in_dma Quick Start Guide for Using DMA with ADC/DAC + * For this examples, see + * \ref asfdoc_sam0_adc_dma_use_case + * \endif + * + * \page asfdoc_sam0_dac_document_revision_history Document Revision History + * + * <table> + * <tr> + * <th>Doc. Rev.</td> + * <th>Date</td> + * <th>Comments</td> + * </tr> + * <tr> + * <td>42450A</td> + * <td>07/2015</td> + * <td>Initial document release</td> + * </tr> + * </table> + */ +#ifdef __cplusplus +} +#endif + + +#endif /* DAC_FEATURE_H_INCLUDED */ +