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Diffstat (limited to 'LUFA/Drivers/Peripheral/AVR8/ADC.h')
| -rw-r--r-- | LUFA/Drivers/Peripheral/AVR8/ADC.h | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/LUFA/Drivers/Peripheral/AVR8/ADC.h b/LUFA/Drivers/Peripheral/AVR8/ADC.h new file mode 100644 index 000000000..99f70d14b --- /dev/null +++ b/LUFA/Drivers/Peripheral/AVR8/ADC.h @@ -0,0 +1,453 @@ +/* + LUFA Library + Copyright (C) Dean Camera, 2011. + + dean [at] fourwalledcubicle [dot] com + www.lufa-lib.org +*/ + +/* + Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com) + + Permission to use, copy, modify, distribute, and sell this + software and its documentation for any purpose is hereby granted + without fee, provided that the above copyright notice appear in + all copies and that both that the copyright notice and this + permission notice and warranty disclaimer appear in supporting + documentation, and that the name of the author not be used in + advertising or publicity pertaining to distribution of the + software without specific, written prior permission. + + The author disclaim all warranties with regard to this + software, including all implied warranties of merchantability + and fitness. In no event shall the author be liable for any + special, indirect or consequential damages or any damages + whatsoever resulting from loss of use, data or profits, whether + in an action of contract, negligence or other tortious action, + arising out of or in connection with the use or performance of + this software. +*/ + +/** \file + * \brief ADC Peripheral Driver (AVR8) + * + * On-chip Analogue-to-Digital converter (ADC) driver for supported U4, U6 and U7 model AVRs that contain an ADC + * peripheral internally. + * + * \note This file should not be included directly. It is automatically included as needed by the ADC driver + * dispatch header located in LUFA/Drivers/Peripheral/ADC.h. + */ + +/** \ingroup Group_ADC + * \defgroup Group_ADC_AVR8 ADC Peripheral Driver (AVR8) + * + * \section Sec_ModDescription Module Description + * On-chip Analogue-to-Digital converter (ADC) driver for supported U4, U6 and U7 model AVRs that contain an ADC + * peripheral internally. + * + * \note This file should not be included directly. It is automatically included as needed by the ADC driver + * dispatch header located in LUFA/Drivers/Peripheral/ADC.h. + * + * \section Sec_ExampleUsage Example Usage + * The following snippet is an example of how this module may be used within a typical + * application. + * + * \code + * // Initialise the ADC driver before first use + * ADC_Init(ADC_FREE_RUNNING | ADC_PRESCALE_32); + * + * // Must setup the ADC channel to read beforehand + * ADC_SetupChannel(1); + * + * // Perform a single conversion of the ADC channel 1 + * ADC_GetChannelReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | ADC_CHANNEL1); + * printf("Conversion Result: %d\r\n", ADC_GetResult()); + * + * // Start reading ADC channel 1 in free running (continuous conversion) mode + * ADC_StartReading(ADC_REFERENCE_AVCC | ADC_RIGHT_ADJUSTED | ADC_CHANNEL1); + * while (!(ADC_IsReadingComplete())) {}; + * printf("Conversion Result: %d\r\n", ADC_GetResult()); + * \endcode + * + * @{ + */ + +#ifndef __ADC_AVR8_H__ +#define __ADC_AVR8_H__ + + /* Includes: */ + #include "../../../Common/Common.h" + + /* Enable C linkage for C++ Compilers: */ + #if defined(__cplusplus) + extern "C" { + #endif + + /* Preprocessor Checks: */ + #if !defined(__INCLUDE_FROM_ADC_H) + #error Do not include this file directly. Include LUFA/Drivers/Peripheral/ADC.h instead. + #endif + + #if !(defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB646__) || \ + defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB647__) || \ + defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || \ + defined(__AVR_ATmega32U6__)) + #error The ADC peripheral driver is not currently available for your selected microcontroller model. + #endif + + /* Private Interface - For use in library only: */ + #if !defined(__DOXYGEN__) + /* Macros: */ + #define _ADC_GET_MUX_MASK2(y) ADC_CHANNEL ## y + #define _ADC_GET_MUX_MASK(y) _ADC_GET_MUX_MASK2(y) + #endif + + /* Public Interface - May be used in end-application: */ + /* Macros: */ + /** \name ADC Reference Configuration Masks */ + //@{ + /** Reference mask, for using the voltage present at the AVR's AREF pin for the ADC reference. */ + #define ADC_REFERENCE_AREF 0 + + /** Reference mask, for using the voltage present at the AVR's AVCC pin for the ADC reference. */ + #define ADC_REFERENCE_AVCC (1 << REFS0) + + /** Reference mask, for using the internally generated 2.56V reference voltage as the ADC reference. */ + #define ADC_REFERENCE_INT2560MV ((1 << REFS1) | (1 << REFS0)) + //@} + + /** \name ADC Result Adjustment Configuration Masks */ + //@{ + /** Left-adjusts the 10-bit ADC result, so that the upper 8 bits of the value returned by the + * \ref ADC_GetResult() macro contain the 8 most significant bits of the result. + */ + #define ADC_LEFT_ADJUSTED (1 << ADLAR) + + /** Right-adjusts the 10-bit ADC result, so that the lower 8 bits of the value returned by the + * \ref ADC_GetResult() macro contain the 8 least significant bits of the result. + */ + #define ADC_RIGHT_ADJUSTED (0 << ADLAR) + //@} + + /** \name ADC Mode Configuration Masks */ + //@{ + /** Sets the ADC mode to free running, so that conversions take place continuously as fast as the ADC + * is capable of at the given input clock speed. + */ + #define ADC_FREE_RUNNING (1 << ADATE) + + /** Sets the ADC mode to single conversion, so that only a single conversion will take place before + * the ADC returns to idle. + */ + #define ADC_SINGLE_CONVERSION (0 << ADATE) + //@} + + /** \name ADC Prescaler Configuration Masks */ + //@{ + /** Sets the ADC input clock to prescale by a factor of 2 the AVR's system clock. */ + #define ADC_PRESCALE_2 (1 << ADPS0) + + /** Sets the ADC input clock to prescale by a factor of 4 the AVR's system clock. */ + #define ADC_PRESCALE_4 (1 << ADPS1) + + /** Sets the ADC input clock to prescale by a factor of 8 the AVR's system clock. */ + #define ADC_PRESCALE_8 ((1 << ADPS0) | (1 << ADPS1)) + + /** Sets the ADC input clock to prescale by a factor of 16 the AVR's system clock. */ + #define ADC_PRESCALE_16 (1 << ADPS2) + + /** Sets the ADC input clock to prescale by a factor of 32 the AVR's system clock. */ + #define ADC_PRESCALE_32 ((1 << ADPS2) | (1 << ADPS0)) + + /** Sets the ADC input clock to prescale by a factor of 64 the AVR's system clock. */ + #define ADC_PRESCALE_64 ((1 << ADPS2) | (1 << ADPS1)) + + /** Sets the ADC input clock to prescale by a factor of 128 the AVR's system clock. */ + #define ADC_PRESCALE_128 ((1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0)) + //@} + + /** \name ADC MUX Masks */ + //@{ + /** MUX mask define for the ADC0 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). */ + #define ADC_CHANNEL0 (0x00 << MUX0) + + /** MUX mask define for the ADC1 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). */ + #define ADC_CHANNEL1 (0x01 << MUX0) + + #if !(defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__)) + /** MUX mask define for the ADC2 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). + * + * \note Not available on all AVR models. + */ + #define ADC_CHANNEL2 (0x02 << MUX0) + + /** MUX mask define for the ADC3 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). + * + * \note Not available on all AVR models. + */ + #define ADC_CHANNEL3 (0x03 << MUX0) + #endif + + /** MUX mask define for the ADC4 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). */ + #define ADC_CHANNEL4 (0x04 << MUX0) + + /** MUX mask define for the ADC5 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). */ + #define ADC_CHANNEL5 (0x05 << MUX0) + + /** MUX mask define for the ADC6 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). */ + #define ADC_CHANNEL6 (0x06 << MUX0) + + /** MUX mask define for the ADC7 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */ + #define ADC_CHANNEL7 (0x07 << MUX0) + + /** MUX mask define for the internal 1.1V bandgap channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). */ + #define ADC_1100MV_BANDGAP (0x1E << MUX0) + + #if (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__)) + /** MUX mask define for the ADC8 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). + * + * \note Not available on all AVR models. + */ + #define ADC_CHANNEL8 ((1 << 8) | (0x00 << MUX0)) + + /** MUX mask define for the ADC9 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). + * + * \note Not available on all AVR models. + */ + #define ADC_CHANNEL9 ((1 << 8) | (0x01 << MUX0)) + + /** MUX mask define for the ADC10 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). + * + * \note Not available on all AVR models. + */ + #define ADC_CHANNEL10 ((1 << 8) | (0x02 << MUX0)) + + /** MUX mask define for the ADC11 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). + * + * \note Not available on all AVR models. + */ + #define ADC_CHANNEL11 ((1 << 8) | (0x03 << MUX0)) + + /** MUX mask define for the ADC12 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). + * + * \note Not available on all AVR models. + */ + #define ADC_CHANNEL12 ((1 << 8) | (0x04 << MUX0)) + + /** MUX mask define for the ADC13 channel of the ADC. See \ref ADC_StartReading() and \ref ADC_GetChannelReading(). + * + * \note Not available on all AVR models. + */ + #define ADC_CHANNEL13 ((1 << 8) | (0x05 << MUX0)) + + /** MUX mask define for the internal temperature sensor channel of the ADC. See \ref ADC_StartReading() and + * \ref ADC_GetChannelReading(). + * + * \note Not available on all AVR models. + */ + #define ADC_INT_TEMP_SENS ((1 << 8) | (0x07 << MUX0)) + #endif + + /** Retrieves the ADC MUX mask for the given ADC channel number. + * + * \note This macro will only work correctly on channel numbers that are compile-time + * constants defined by the preprocessor. + * + * \param[in] Channel Index of the ADC channel whose MUX mask is to be retrieved. + */ + #define ADC_GET_CHANNEL_MASK(Channel) _ADC_GET_MUX_MASK(Channel) + //@} + + /* Inline Functions: */ + /** Configures the given ADC channel, ready for ADC conversions. This function sets the + * associated port pin as an input and disables the digital portion of the I/O to reduce + * power consumption. + * + * \note This must only be called for ADC channels with are connected to a physical port + * pin of the AVR, denoted by its special alternative function ADCx. + * \n\n + * + * \note The channel number must be specified as an integer, and <b>not</b> a \c ADC_CHANNEL* mask. + * + * \param[in] ChannelIndex ADC channel number to set up for conversions. + */ + static inline void ADC_SetupChannel(const uint8_t ChannelIndex) + { + #if (defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB646__) || \ + defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB647__) || \ + defined(__AVR_ATmega32U6__)) + DDRF &= ~(1 << ChannelIndex); + DIDR0 |= (1 << ChannelIndex); + #elif (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__)) + if (ChannelIndex < 8) + { + DDRF &= ~(1 << ChannelIndex); + DIDR0 |= (1 << ChannelIndex); + } + else if (ChannelIndex == 8) + { + DDRD &= ~(1 << 4); + DIDR2 |= (1 << 0); + } + else if (ChannelIndex < 11) + { + DDRD &= ~(1 << (ChannelIndex - 3)); + DIDR2 |= (1 << (ChannelIndex - 8)); + } + else + { + DDRB &= ~(1 << (ChannelIndex - 7)); + DIDR2 |= (1 << (ChannelIndex - 8)); + } + #endif + } + + /** De-configures the given ADC channel, re-enabling digital I/O mode instead of analog. This + * function sets the associated port pin as an input and re-enabled the digital portion of + * the I/O. + * + * \note This must only be called for ADC channels with are connected to a physical port + * pin of the AVR, denoted by its special alternative function ADCx. + * \n\n + * + * \note The channel number must be specified as an integer, and <b>not</b> a \c ADC_CHANNEL* mask. + * + * \param[in] ChannelIndex ADC channel number to set up for conversions. + */ + static inline void ADC_DisableChannel(const uint8_t ChannelIndex) + { + #if (defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB646__) || \ + defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB647__) || \ + defined(__AVR_ATmega32U6__)) + DDRF &= ~(1 << ChannelIndex); + DIDR0 &= ~(1 << ChannelIndex); + #elif (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__)) + if (ChannelIndex < 8) + { + DDRF &= ~(1 << ChannelIndex); + DIDR0 &= ~(1 << ChannelIndex); + } + else if (ChannelIndex == 8) + { + DDRD &= ~(1 << 4); + DIDR2 &= ~(1 << 0); + } + else if (ChannelIndex < 11) + { + DDRD &= ~(1 << (ChannelIndex - 3)); + DIDR2 &= ~(1 << (ChannelIndex - 8)); + } + else + { + DDRB &= ~(1 << (ChannelIndex - 7)); + DIDR2 &= ~(1 << (ChannelIndex - 8)); + } + #endif + } + + /** Starts the reading of the given channel, but does not wait until the conversion has completed. + * Once executed, the conversion status can be determined via the \ref ADC_IsReadingComplete() macro and + * the result read via the \ref ADC_GetResult() macro. + * + * If the ADC has been initialized in free running mode, calling this function once will begin the repeated + * conversions. If the ADC is in single conversion mode (or the channel to convert from is to be changed), + * this function must be called each time a conversion is to take place. + * + * \param[in] MUXMask ADC channel mask, reference mask and adjustment mask. + */ + static inline void ADC_StartReading(const uint16_t MUXMask) + { + ADMUX = MUXMask; + + #if (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__)) + if (MUXMask & (1 << 8)) + ADCSRB |= (1 << MUX5); + else + ADCSRB &= ~(1 << MUX5); + #endif + + ADCSRA |= (1 << ADSC); + } + + /** Indicates if the current ADC conversion is completed, or still in progress. + * + * \return Boolean false if the reading is still taking place, or true if the conversion is + * complete and ready to be read out with \ref ADC_GetResult(). + */ + static inline bool ADC_IsReadingComplete(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE; + static inline bool ADC_IsReadingComplete(void) + { + return ((ADCSRA & (1 << ADIF)) ? true : false); + } + + /** Retrieves the conversion value of the last completed ADC conversion and clears the reading + * completion flag. + * + * \return The result of the last ADC conversion as an unsigned value. + */ + static inline uint16_t ADC_GetResult(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE; + static inline uint16_t ADC_GetResult(void) + { + ADCSRA |= (1 << ADIF); + return ADC; + } + + /** Performs a complete single reading from channel, including a polling spin-loop to wait for the + * conversion to complete, and the returning of the converted value. + * + * \note For free running mode, the automated conversions should be initialized with a single call + * to \ref ADC_StartReading() to select the channel and begin the automated conversions, and + * the results read directly from the \ref ADC_GetResult() instead to reduce overhead. + * + * \param[in] MUXMask Mask comprising of an ADC channel mask, reference mask and adjustment mask. + */ + static inline uint16_t ADC_GetChannelReading(const uint16_t MUXMask) ATTR_WARN_UNUSED_RESULT; + static inline uint16_t ADC_GetChannelReading(const uint16_t MUXMask) + { + ADC_StartReading(MUXMask); + + while (!(ADC_IsReadingComplete())); + + return ADC_GetResult(); + } + + /** Initialises the ADC, ready for conversions. This must be called before any other ADC operations. + * The "mode" parameter should be a mask comprised of a conversion mode (free running or single) and + * prescaler masks. + * + * \param[in] Mode Mask of ADC prescale and mode settings. + */ + static inline void ADC_Init(uint8_t Mode) ATTR_ALWAYS_INLINE; + static inline void ADC_Init(uint8_t Mode) + { + ADCSRA = ((1 << ADEN) | Mode); + } + + /** Turns off the ADC. If this is called, any further ADC operations will require a call to + * \ref ADC_Init() before the ADC can be used again. + */ + static inline void ADC_Disable(void) ATTR_ALWAYS_INLINE; + static inline void ADC_Disable(void) + { + ADCSRA = 0; + } + + /** Indicates if the ADC is currently enabled. + * + * \return Boolean \c true if the ADC subsystem is currently enabled, \c false otherwise. + */ + static inline bool ADC_GetStatus(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE; + static inline bool ADC_GetStatus(void) + { + return ((ADCSRA & (1 << ADEN)) ? true : false); + } + + /* Disable C linkage for C++ Compilers: */ + #if defined(__cplusplus) + } + #endif + +#endif + +/** @} */ + |