LUFA/Drivers/Peripheral/AVRU4U6U7/ADC.h

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2010.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2010  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 /** \file
  32  *  \brief ADC peripheral driver for the U7, U6 and U4 USB AVRs.
  33  *
  34  *  On-chip Analogue-to-Digital converter (ADC) driver for supported U4, U6 and U7 model AVRs that contain an ADC
  35  *  peripheral internally.
  36  *
  37  *  \note This file should not be included directly. It is automatically included as needed by the ADC driver
  38  *        dispatch header located in LUFA/Drivers/Peripheral/ADC.h.
  39  */
  40
  41 /** \ingroup Group_ADC
  42  *  @defgroup Group_ADC_AVRU4U6U7 Series U4, U6 and U7 Model ADC Driver
  43  *
  44  *  On-chip Analogue-to-Digital converter (ADC) driver for supported U4, U6 and U7 model AVRs that contain an ADC
  45  *  peripheral internally.
  46  *
  47  *  \note This file should not be included directly. It is automatically included as needed by the ADC driver
  48  *        dispatch header located in LUFA/Drivers/Peripheral/ADC.h.
  49  *
  50  *  @{
  51  */
  52
  53 #ifndef __ADC_AVRU4U6U7_H__
  54 #define __ADC_AVRU4U6U7_H__
  55
  56         /* Includes: */
  57                 #include "../../../Common/Common.h"
  58
  59                 #include <avr/io.h>
  60                 #include <stdbool.h>
  61
  62         /* Enable C linkage for C++ Compilers: */
  63                 #if defined(__cplusplus)
  64                         extern "C" {
  65                 #endif
  66
  67         /* Preprocessor Checks: */
  68                 #if !defined(__INCLUDE_FROM_ADC_H)
  69                         #error Do not include this file directly. Include LUFA/Drivers/Peripheral/ADC.h instead.
  70                 #endif
  71
  72         /* Public Interface - May be used in end-application: */
  73                 /* Macros: */
  74                         /** Reference mask, for using the voltage present at the AVR's AREF pin for the ADC reference. */
  75                         #define ADC_REFERENCE_AREF              0
  76
  77                         /** Reference mask, for using the voltage present at the AVR's AVCC pin for the ADC reference. */
  78                         #define ADC_REFERENCE_AVCC              (1 << REFS0)
  79
  80                         /** Reference mask, for using the internally generated 2.56V reference voltage as the ADC reference. */
  81                         #define ADC_REFERENCE_INT2560MV         ((1 << REFS1) | (1 << REFS0))
  82
  83                         /** Left-adjusts the 10-bit ADC result, so that the upper 8 bits of the value returned by the
  84                          *  ADC_GetResult() macro contain the 8 most significant bits of the result. */
  85                         #define ADC_LEFT_ADJUSTED               (1 << ADLAR)
  86
  87                         /** Right-adjusts the 10-bit ADC result, so that the lower 8 bits of the value returned by the
  88                          *  ADC_GetResult() macro contain the 8 least significant bits of the result. */
  89                         #define ADC_RIGHT_ADJUSTED              (0 << ADLAR)
  90
  91                         /** Sets the ADC mode to free running, so that conversions take place continuously as fast as the ADC
  92                          *  is capable of at the given input clock speed. */
  93                         #define ADC_FREE_RUNNING                (1 << ADATE)
  94
  95                         /** Sets the ADC mode to single conversion, so that only a single conversion will take place before
  96                          *  the ADC returns to idle. */
  97                         #define ADC_SINGLE_CONVERSION           (0 << ADATE)
  98
  99                         /** Sets the ADC input clock to prescale by a factor of 2 the AVR's system clock. */
 100                         #define ADC_PRESCALE_2                  (1 << ADPS0)
 101
 102                         /** Sets the ADC input clock to prescale by a factor of 4 the AVR's system clock. */
 103                         #define ADC_PRESCALE_4                  (1 << ADPS1)
 104
 105                         /** Sets the ADC input clock to prescale by a factor of 8 the AVR's system clock. */
 106                         #define ADC_PRESCALE_8                  ((1 << ADPS0) | (1 << ADPS1))
 107
 108                         /** Sets the ADC input clock to prescale by a factor of 16 the AVR's system clock. */
 109                         #define ADC_PRESCALE_16                 (1 << ADPS2)
 110
 111                         /** Sets the ADC input clock to prescale by a factor of 32 the AVR's system clock. */
 112                         #define ADC_PRESCALE_32                 ((1 << ADPS2) | (1 << ADPS0))
 113
 114                         /** Sets the ADC input clock to prescale by a factor of 64 the AVR's system clock. */
 115                         #define ADC_PRESCALE_64                 ((1 << ADPS2) | (1 << ADPS1))
 116
 117                         /** Sets the ADC input clock to prescale by a factor of 128 the AVR's system clock. */
 118                         #define ADC_PRESCALE_128                ((1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0))
 119
 120                         //@{
 121                         /** MUX mask define for the ADC0 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 122                         #define ADC_CHANNEL0                    (0x00 << MUX0)
 123
 124                         /** MUX mask define for the ADC1 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 125                         #define ADC_CHANNEL1                    (0x01 << MUX0)
 126
 127                         #if !(defined(__AVR_ATmega16U4__)  || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__))
 128                                 /** MUX mask define for the ADC2 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 129                                  *
 130                                  *  \note Not available on all AVR models.
 131                                  */
 132                                 #define ADC_CHANNEL2                (0x02 << MUX0)
 133
 134                                 /** MUX mask define for the ADC3 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 135                                  *
 136                                  *  \note Not available on all AVR models.
 137                                  */
 138                                 #define ADC_CHANNEL3                (0x03 << MUX0)
 139                         #endif
 140
 141                         /** MUX mask define for the ADC4 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 142                         #define ADC_CHANNEL4                    (0x04 << MUX0)
 143
 144                         /** MUX mask define for the ADC5 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 145                         #define ADC_CHANNEL5                    (0x05 << MUX0)
 146
 147                         /** MUX mask define for the ADC6 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 148                         #define ADC_CHANNEL6                    (0x06 << MUX0)
 149
 150                         /** MUX mask define for the ADC7 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 151                         #define ADC_CHANNEL7                    (0x07 << MUX0)
 152
 153                         /** MUX mask define for the internal 1.1V bandgap channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 154                         #define ADC_1100MV_BANDGAP              (0x1E << MUX0)
 155
 156                         #if (defined(__AVR_ATmega16U4__)  || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__))
 157                                 /** MUX mask define for the ADC8 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 158                                  *
 159                                  *  \note Not available on all AVR models.
 160                                  */
 161                                 #define ADC_CHANNEL8                ((1 << 8) | (0x00 << MUX0))
 162
 163                                 /** MUX mask define for the ADC9 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 164                                  *
 165                                  *  \note Not available on all AVR models.
 166                                  */
 167                                 #define ADC_CHANNEL9                ((1 << 8) | (0x01 << MUX0))
 168
 169                                 /** MUX mask define for the ADC10 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 170                                  *
 171                                  *  \note Not available on all AVR models.
 172                                  */
 173                                 #define ADC_CHANNEL10               ((1 << 8) | (0x02 << MUX0))
 174
 175                                 /** MUX mask define for the ADC11 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 176                                  *
 177                                  *  \note Not available on all AVR models.
 178                                  */
 179                                 #define ADC_CHANNEL11               ((1 << 8) | (0x03 << MUX0))
 180
 181                                 /** MUX mask define for the ADC12 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 182                                  *
 183                                  *  \note Not available on all AVR models.
 184                                  */
 185                                 #define ADC_CHANNEL12               ((1 << 8) | (0x04 << MUX0))
 186
 187                                 /** MUX mask define for the ADC13 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 188                                  *
 189                                  *  \note Not available on all AVR models.
 190                                  */
 191                                 #define ADC_CHANNEL13               ((1 << 8) | (0x05 << MUX0))
 192
 193                                 /** MUX mask define for the internal temperature sensor channel of the ADC. See \ref ADC_StartReading and
 194                                  *  \ref ADC_GetChannelReading.
 195                                  *
 196                                  *  \note Not available on all AVR models.
 197                                  */
 198                                 #define ADC_INT_TEMP_SENS           ((1 << 8) | (0x07 << MUX0))
 199                         #endif
 200                         //@}
 201
 202                 /* Inline Functions: */
 203                         /** Configures the given ADC channel, ready for ADC conversions. This function sets the
 204                          *  associated port pin as an input and disables the digital portion of the I/O to reduce
 205                          *  power consumption.
 206                          *
 207                          *  \note This must only be called for ADC channels with are connected to a physical port
 208                          *        pin of the AVR, denoted by its special alternative function ADCx.
 209                          *        \n\n
 210                          *
 211                          *  \note The channel number must be specified as an integer, and NOT a ADC_CHANNELx mask.
 212                          *
 213                          *  \param[in] ChannelIndex  ADC channel number to set up for conversions.
 214                          */
 215                         static inline void ADC_SetupChannel(const uint8_t ChannelIndex)
 216                         {
 217                                 #if (defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB646__) || \
 218                                          defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB647__) || \
 219                                          defined(__AVR_ATmega32U6__))
 220                                 DDRF  &= ~(1 << ChannelIndex);
 221                                 DIDR0 |=  (1 << ChannelIndex);
 222                                 #elif (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
 223                                 if (ChannelIndex < 8)
 224                                 {
 225                                         DDRF  &= ~(1 << ChannelIndex);
 226                                         DIDR0 |=  (1 << ChannelIndex);
 227                                 }
 228                                 else if (ChannelIndex == 8)
 229                                 {
 230                                         DDRD  &= ~(1 << 4);
 231                                         DIDR2 |=  (1 << 0);
 232                                 }
 233                                 else if (ChannelIndex < 11)
 234                                 {
 235                                         DDRD  &= ~(1 << (ChannelIndex - 3));
 236                                         DIDR2 |=  (1 << (ChannelIndex - 8));
 237                                 }
 238                                 else
 239                                 {
 240                                         DDRB  &= ~(1 << (ChannelIndex - 7));
 241                                         DIDR2 |=  (1 << (ChannelIndex - 8));
 242                                 }
 243                                 #endif
 244                         }
 245
 246                         /** De-configures the given ADC channel, re-enabling digital I/O mode instead of analog. This
 247                          *  function sets the associated port pin as an input and re-enabled the digital portion of
 248                          *  the I/O.
 249                          *
 250                          *  \note This must only be called for ADC channels with are connected to a physical port
 251                          *        pin of the AVR, denoted by its special alternative function ADCx.
 252                          *        \n\n
 253                          *
 254                          *  \note The channel number must be specified as an integer, and NOT a ADC_CHANNELx mask.
 255                          *
 256                          *  \param[in] ChannelIndex  ADC channel number to set up for conversions.
 257                          */
 258                         static inline void ADC_DisableChannel(const uint8_t ChannelIndex)
 259                         {
 260                                 #if (defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB646__) || \
 261                                          defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB647__) || \
 262                                          defined(__AVR_ATmega32U6__))
 263                                 DDRF  &= ~(1 << ChannelIndex);
 264                                 DIDR0 &= ~(1 << ChannelIndex);
 265                                 #elif (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
 266                                 if (ChannelIndex < 8)
 267                                 {
 268                                         DDRF  &= ~(1 << ChannelIndex);
 269                                         DIDR0 &= ~(1 << ChannelIndex);
 270                                 }
 271                                 else if (ChannelIndex == 8)
 272                                 {
 273                                         DDRD  &= ~(1 << 4);
 274                                         DIDR2 &= ~(1 << 0);
 275                                 }
 276                                 else if (ChannelIndex < 11)
 277                                 {
 278                                         DDRD  &= ~(1 << (ChannelIndex - 3));
 279                                         DIDR2 &= ~(1 << (ChannelIndex - 8));
 280                                 }
 281                                 else
 282                                 {
 283                                         DDRB  &= ~(1 << (ChannelIndex - 7));
 284                                         DIDR2 &= ~(1 << (ChannelIndex - 8));
 285                                 }
 286                                 #endif
 287                         }
 288
 289                         /** Starts the reading of the given channel, but does not wait until the conversion has completed.
 290                          *  Once executed, the conversion status can be determined via the \ref ADC_IsReadingComplete() macro and
 291                          *  the result read via the \ref ADC_GetResult() macro.
 292                          *
 293                          *  If the ADC has been initialized in free running mode, calling this function once will begin the repeated
 294                          *  conversions. If the ADC is in single conversion mode (or the channel to convert from is to be changed),
 295                          *  this function must be called each time a conversion is to take place.
 296                          *
 297                          *  \param[in] MUXMask  ADC channel mask, reference mask and adjustment mask.
 298                          */
 299                         static inline void ADC_StartReading(const uint16_t MUXMask)
 300                         {
 301                                 ADMUX = MUXMask;
 302
 303                                 #if (defined(__AVR_ATmega16U4__)  || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__))
 304                                 if (MUXMask & (1 << 8))
 305                                   ADCSRB |=  (1 << MUX5);
 306                                 else
 307                                   ADCSRB &= ~(1 << MUX5);
 308                                 #endif
 309
 310                                 ADCSRA |= (1 << ADSC);
 311                         }
 312
 313                         /** Indicates if the current ADC conversion is completed, or still in progress.
 314                          *
 315                          *  \return Boolean false if the reading is still taking place, or true if the conversion is
 316                          *          complete and ready to be read out with \ref ADC_GetResult().
 317                          */
 318                         static inline bool ADC_IsReadingComplete(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
 319                         static inline bool ADC_IsReadingComplete(void)
 320                         {
 321                                 return ((ADCSRA & (1 << ADIF)) ? true : false);
 322                         }
 323
 324                         /** Retrieves the conversion value of the last completed ADC conversion and clears the reading
 325                          *  completion flag.
 326                          *
 327                          *  \return The result of the last ADC conversion as an unsigned value.
 328                          */
 329                         static inline uint16_t ADC_GetResult(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
 330                         static inline uint16_t ADC_GetResult(void)
 331                         {
 332                                 ADCSRA |= (1 << ADIF);
 333                                 return ADC;
 334                         }
 335
 336                         /** Performs a complete single reading from channel, including a polling spin-loop to wait for the
 337                          *  conversion to complete, and the returning of the converted value.
 338                          *
 339                          *  \note For free running mode, the automated conversions should be initialized with a single call
 340                          *        to \ref ADC_StartReading() to select the channel and begin the automated conversions, and
 341                          *        the results read directly from the \ref ADC_GetResult() instead to reduce overhead.
 342                          *
 343                          *  \param[in] MUXMask  Mask comprising of an ADC channel mask, reference mask and adjustment mask.
 344                          */
 345                         static inline uint16_t ADC_GetChannelReading(const uint16_t MUXMask) ATTR_WARN_UNUSED_RESULT;
 346                         static inline uint16_t ADC_GetChannelReading(const uint16_t MUXMask)
 347                         {
 348                                 ADC_StartReading(MUXMask);
 349
 350                                 while (!(ADC_IsReadingComplete()));
 351
 352                                 return ADC_GetResult();
 353                         }
 354
 355                         /** Initialises the ADC, ready for conversions. This must be called before any other ADC operations.
 356                          *  The "mode" parameter should be a mask comprised of a conversion mode (free running or single) and
 357                          *  prescaler masks.
 358                          *
 359                          *  \param[in] Mode  Mask of ADC prescale and mode settings.
 360                          */
 361                         static inline void ADC_Init(uint8_t Mode) ATTR_ALWAYS_INLINE;
 362                         static inline void ADC_Init(uint8_t Mode)
 363                         {
 364                                 ADCSRA = ((1 << ADEN) | Mode);
 365                         }
 366
 367                         /** Turns off the ADC. If this is called, any further ADC operations will require a call to
 368                          *  \ref ADC_Init() before the ADC can be used again.
 369                          */
 370                         static inline void ADC_ShutDown(void) ATTR_ALWAYS_INLINE;
 371                         static inline void ADC_ShutDown(void)
 372                         {
 373                                 ADCSRA = 0;
 374                         }
 375
 376                         /** Indicates if the ADC is currently enabled.
 377                          *
 378                          *  \return Boolean true if the ADC subsystem is currently enabled, false otherwise.
 379                          */
 380                         static inline bool ADC_GetStatus(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
 381                         static inline bool ADC_GetStatus(void)
 382                         {
 383                                 return ((ADCSRA & (1 << ADEN)) ? true : false);
 384                         }
 385
 386         /* Disable C linkage for C++ Compilers: */
 387                 #if defined(__cplusplus)
 388                         }
 389                 #endif
 390
 391 #endif
 392
 393 /** @} */