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.lufa-lib.org
   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                         /** \name ADC Reference Configuration Masks */
  75                         //@{
  76                         /** Reference mask, for using the voltage present at the AVR's AREF pin for the ADC reference. */
  77                         #define ADC_REFERENCE_AREF              0
  78
  79                         /** Reference mask, for using the voltage present at the AVR's AVCC pin for the ADC reference. */
  80                         #define ADC_REFERENCE_AVCC              (1 << REFS0)
  81
  82                         /** Reference mask, for using the internally generated 2.56V reference voltage as the ADC reference. */
  83                         #define ADC_REFERENCE_INT2560MV         ((1 << REFS1) | (1 << REFS0))
  84                         //@}
  85
  86                         /** \name ADC Result Adjustment Configuration Masks */
  87                         //@{
  88                         /** Left-adjusts the 10-bit ADC result, so that the upper 8 bits of the value returned by the
  89                          *  ADC_GetResult() macro contain the 8 most significant bits of the result.
  90                          */
  91                         #define ADC_LEFT_ADJUSTED               (1 << ADLAR)
  92
  93                         /** Right-adjusts the 10-bit ADC result, so that the lower 8 bits of the value returned by the
  94                          *  ADC_GetResult() macro contain the 8 least significant bits of the result.
  95                          */
  96                         #define ADC_RIGHT_ADJUSTED              (0 << ADLAR)
  97                         //@}
  98
  99                         /** \name ADC Mode Configuration Masks */
 100                         //@{
 101                         /** Sets the ADC mode to free running, so that conversions take place continuously as fast as the ADC
 102                          *  is capable of at the given input clock speed.
 103                          */
 104                         #define ADC_FREE_RUNNING                (1 << ADATE)
 105
 106                         /** Sets the ADC mode to single conversion, so that only a single conversion will take place before
 107                          *  the ADC returns to idle.
 108                          */
 109                         #define ADC_SINGLE_CONVERSION           (0 << ADATE)
 110                         //@}
 111
 112                         /** \name ADC Prescaler Configuration Masks */
 113                         //@{
 114                         /** Sets the ADC input clock to prescale by a factor of 2 the AVR's system clock. */
 115                         #define ADC_PRESCALE_2                  (1 << ADPS0)
 116
 117                         /** Sets the ADC input clock to prescale by a factor of 4 the AVR's system clock. */
 118                         #define ADC_PRESCALE_4                  (1 << ADPS1)
 119
 120                         /** Sets the ADC input clock to prescale by a factor of 8 the AVR's system clock. */
 121                         #define ADC_PRESCALE_8                  ((1 << ADPS0) | (1 << ADPS1))
 122
 123                         /** Sets the ADC input clock to prescale by a factor of 16 the AVR's system clock. */
 124                         #define ADC_PRESCALE_16                 (1 << ADPS2)
 125
 126                         /** Sets the ADC input clock to prescale by a factor of 32 the AVR's system clock. */
 127                         #define ADC_PRESCALE_32                 ((1 << ADPS2) | (1 << ADPS0))
 128
 129                         /** Sets the ADC input clock to prescale by a factor of 64 the AVR's system clock. */
 130                         #define ADC_PRESCALE_64                 ((1 << ADPS2) | (1 << ADPS1))
 131
 132                         /** Sets the ADC input clock to prescale by a factor of 128 the AVR's system clock. */
 133                         #define ADC_PRESCALE_128                ((1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0))
 134                         //@}
 135
 136                         /** \name ADC MUX Masks */
 137                         //@{
 138                         /** MUX mask define for the ADC0 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 139                         #define ADC_CHANNEL0                    (0x00 << MUX0)
 140
 141                         /** MUX mask define for the ADC1 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 142                         #define ADC_CHANNEL1                    (0x01 << MUX0)
 143
 144                         #if !(defined(__AVR_ATmega16U4__)  || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__))
 145                                 /** MUX mask define for the ADC2 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 146                                  *
 147                                  *  \note Not available on all AVR models.
 148                                  */
 149                                 #define ADC_CHANNEL2                (0x02 << MUX0)
 150
 151                                 /** MUX mask define for the ADC3 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 152                                  *
 153                                  *  \note Not available on all AVR models.
 154                                  */
 155                                 #define ADC_CHANNEL3                (0x03 << MUX0)
 156                         #endif
 157
 158                         /** MUX mask define for the ADC4 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 159                         #define ADC_CHANNEL4                    (0x04 << MUX0)
 160
 161                         /** MUX mask define for the ADC5 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 162                         #define ADC_CHANNEL5                    (0x05 << MUX0)
 163
 164                         /** MUX mask define for the ADC6 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 165                         #define ADC_CHANNEL6                    (0x06 << MUX0)
 166
 167                         /** MUX mask define for the ADC7 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 168                         #define ADC_CHANNEL7                    (0x07 << MUX0)
 169
 170                         /** MUX mask define for the internal 1.1V bandgap channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
 171                         #define ADC_1100MV_BANDGAP              (0x1E << MUX0)
 172
 173                         #if (defined(__AVR_ATmega16U4__)  || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__))
 174                                 /** MUX mask define for the ADC8 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 175                                  *
 176                                  *  \note Not available on all AVR models.
 177                                  */
 178                                 #define ADC_CHANNEL8                ((1 << 8) | (0x00 << MUX0))
 179
 180                                 /** MUX mask define for the ADC9 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 181                                  *
 182                                  *  \note Not available on all AVR models.
 183                                  */
 184                                 #define ADC_CHANNEL9                ((1 << 8) | (0x01 << MUX0))
 185
 186                                 /** MUX mask define for the ADC10 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 187                                  *
 188                                  *  \note Not available on all AVR models.
 189                                  */
 190                                 #define ADC_CHANNEL10               ((1 << 8) | (0x02 << MUX0))
 191
 192                                 /** MUX mask define for the ADC11 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 193                                  *
 194                                  *  \note Not available on all AVR models.
 195                                  */
 196                                 #define ADC_CHANNEL11               ((1 << 8) | (0x03 << MUX0))
 197
 198                                 /** MUX mask define for the ADC12 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 199                                  *
 200                                  *  \note Not available on all AVR models.
 201                                  */
 202                                 #define ADC_CHANNEL12               ((1 << 8) | (0x04 << MUX0))
 203
 204                                 /** MUX mask define for the ADC13 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
 205                                  *
 206                                  *  \note Not available on all AVR models.
 207                                  */
 208                                 #define ADC_CHANNEL13               ((1 << 8) | (0x05 << MUX0))
 209
 210                                 /** MUX mask define for the internal temperature sensor channel of the ADC. See \ref ADC_StartReading and
 211                                  *  \ref ADC_GetChannelReading.
 212                                  *
 213                                  *  \note Not available on all AVR models.
 214                                  */
 215                                 #define ADC_INT_TEMP_SENS           ((1 << 8) | (0x07 << MUX0))
 216                         #endif
 217                         //@}
 218
 219                 /* Inline Functions: */
 220                         /** Configures the given ADC channel, ready for ADC conversions. This function sets the
 221                          *  associated port pin as an input and disables the digital portion of the I/O to reduce
 222                          *  power consumption.
 223                          *
 224                          *  \note This must only be called for ADC channels with are connected to a physical port
 225                          *        pin of the AVR, denoted by its special alternative function ADCx.
 226                          *        \n\n
 227                          *
 228                          *  \note The channel number must be specified as an integer, and NOT a ADC_CHANNELx mask.
 229                          *
 230                          *  \param[in] ChannelIndex  ADC channel number to set up for conversions.
 231                          */
 232                         static inline void ADC_SetupChannel(const uint8_t ChannelIndex)
 233                         {
 234                                 #if (defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB646__) || \
 235                                          defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB647__) || \
 236                                          defined(__AVR_ATmega32U6__))
 237                                 DDRF  &= ~(1 << ChannelIndex);
 238                                 DIDR0 |=  (1 << ChannelIndex);
 239                                 #elif (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
 240                                 if (ChannelIndex < 8)
 241                                 {
 242                                         DDRF  &= ~(1 << ChannelIndex);
 243                                         DIDR0 |=  (1 << ChannelIndex);
 244                                 }
 245                                 else if (ChannelIndex == 8)
 246                                 {
 247                                         DDRD  &= ~(1 << 4);
 248                                         DIDR2 |=  (1 << 0);
 249                                 }
 250                                 else if (ChannelIndex < 11)
 251                                 {
 252                                         DDRD  &= ~(1 << (ChannelIndex - 3));
 253                                         DIDR2 |=  (1 << (ChannelIndex - 8));
 254                                 }
 255                                 else
 256                                 {
 257                                         DDRB  &= ~(1 << (ChannelIndex - 7));
 258                                         DIDR2 |=  (1 << (ChannelIndex - 8));
 259                                 }
 260                                 #endif
 261                         }
 262
 263                         /** De-configures the given ADC channel, re-enabling digital I/O mode instead of analog. This
 264                          *  function sets the associated port pin as an input and re-enabled the digital portion of
 265                          *  the I/O.
 266                          *
 267                          *  \note This must only be called for ADC channels with are connected to a physical port
 268                          *        pin of the AVR, denoted by its special alternative function ADCx.
 269                          *        \n\n
 270                          *
 271                          *  \note The channel number must be specified as an integer, and NOT a ADC_CHANNELx mask.
 272                          *
 273                          *  \param[in] ChannelIndex  ADC channel number to set up for conversions.
 274                          */
 275                         static inline void ADC_DisableChannel(const uint8_t ChannelIndex)
 276                         {
 277                                 #if (defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB646__) || \
 278                                          defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB647__) || \
 279                                          defined(__AVR_ATmega32U6__))
 280                                 DDRF  &= ~(1 << ChannelIndex);
 281                                 DIDR0 &= ~(1 << ChannelIndex);
 282                                 #elif (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
 283                                 if (ChannelIndex < 8)
 284                                 {
 285                                         DDRF  &= ~(1 << ChannelIndex);
 286                                         DIDR0 &= ~(1 << ChannelIndex);
 287                                 }
 288                                 else if (ChannelIndex == 8)
 289                                 {
 290                                         DDRD  &= ~(1 << 4);
 291                                         DIDR2 &= ~(1 << 0);
 292                                 }
 293                                 else if (ChannelIndex < 11)
 294                                 {
 295                                         DDRD  &= ~(1 << (ChannelIndex - 3));
 296                                         DIDR2 &= ~(1 << (ChannelIndex - 8));
 297                                 }
 298                                 else
 299                                 {
 300                                         DDRB  &= ~(1 << (ChannelIndex - 7));
 301                                         DIDR2 &= ~(1 << (ChannelIndex - 8));
 302                                 }
 303                                 #endif
 304                         }
 305
 306                         /** Starts the reading of the given channel, but does not wait until the conversion has completed.
 307                          *  Once executed, the conversion status can be determined via the \ref ADC_IsReadingComplete() macro and
 308                          *  the result read via the \ref ADC_GetResult() macro.
 309                          *
 310                          *  If the ADC has been initialized in free running mode, calling this function once will begin the repeated
 311                          *  conversions. If the ADC is in single conversion mode (or the channel to convert from is to be changed),
 312                          *  this function must be called each time a conversion is to take place.
 313                          *
 314                          *  \param[in] MUXMask  ADC channel mask, reference mask and adjustment mask.
 315                          */
 316                         static inline void ADC_StartReading(const uint16_t MUXMask)
 317                         {
 318                                 ADMUX = MUXMask;
 319
 320                                 #if (defined(__AVR_ATmega16U4__)  || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__))
 321                                 if (MUXMask & (1 << 8))
 322                                   ADCSRB |=  (1 << MUX5);
 323                                 else
 324                                   ADCSRB &= ~(1 << MUX5);
 325                                 #endif
 326
 327                                 ADCSRA |= (1 << ADSC);
 328                         }
 329
 330                         /** Indicates if the current ADC conversion is completed, or still in progress.
 331                          *
 332                          *  \return Boolean false if the reading is still taking place, or true if the conversion is
 333                          *          complete and ready to be read out with \ref ADC_GetResult().
 334                          */
 335                         static inline bool ADC_IsReadingComplete(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
 336                         static inline bool ADC_IsReadingComplete(void)
 337                         {
 338                                 return ((ADCSRA & (1 << ADIF)) ? true : false);
 339                         }
 340
 341                         /** Retrieves the conversion value of the last completed ADC conversion and clears the reading
 342                          *  completion flag.
 343                          *
 344                          *  \return The result of the last ADC conversion as an unsigned value.
 345                          */
 346                         static inline uint16_t ADC_GetResult(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
 347                         static inline uint16_t ADC_GetResult(void)
 348                         {
 349                                 ADCSRA |= (1 << ADIF);
 350                                 return ADC;
 351                         }
 352
 353                         /** Performs a complete single reading from channel, including a polling spin-loop to wait for the
 354                          *  conversion to complete, and the returning of the converted value.
 355                          *
 356                          *  \note For free running mode, the automated conversions should be initialized with a single call
 357                          *        to \ref ADC_StartReading() to select the channel and begin the automated conversions, and
 358                          *        the results read directly from the \ref ADC_GetResult() instead to reduce overhead.
 359                          *
 360                          *  \param[in] MUXMask  Mask comprising of an ADC channel mask, reference mask and adjustment mask.
 361                          */
 362                         static inline uint16_t ADC_GetChannelReading(const uint16_t MUXMask) ATTR_WARN_UNUSED_RESULT;
 363                         static inline uint16_t ADC_GetChannelReading(const uint16_t MUXMask)
 364                         {
 365                                 ADC_StartReading(MUXMask);
 366
 367                                 while (!(ADC_IsReadingComplete()));
 368
 369                                 return ADC_GetResult();
 370                         }
 371
 372                         /** Initialises the ADC, ready for conversions. This must be called before any other ADC operations.
 373                          *  The "mode" parameter should be a mask comprised of a conversion mode (free running or single) and
 374                          *  prescaler masks.
 375                          *
 376                          *  \param[in] Mode  Mask of ADC prescale and mode settings.
 377                          */
 378                         static inline void ADC_Init(uint8_t Mode) ATTR_ALWAYS_INLINE;
 379                         static inline void ADC_Init(uint8_t Mode)
 380                         {
 381                                 ADCSRA = ((1 << ADEN) | Mode);
 382                         }
 383
 384                         /** Turns off the ADC. If this is called, any further ADC operations will require a call to
 385                          *  \ref ADC_Init() before the ADC can be used again.
 386                          */
 387                         static inline void ADC_ShutDown(void) ATTR_ALWAYS_INLINE;
 388                         static inline void ADC_ShutDown(void)
 389                         {
 390                                 ADCSRA = 0;
 391                         }
 392
 393                         /** Indicates if the ADC is currently enabled.
 394                          *
 395                          *  \return Boolean true if the ADC subsystem is currently enabled, false otherwise.
 396                          */
 397                         static inline bool ADC_GetStatus(void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
 398                         static inline bool ADC_GetStatus(void)
 399                         {
 400                                 return ((ADCSRA & (1 << ADEN)) ? true : false);
 401                         }
 402
 403         /* Disable C linkage for C++ Compilers: */
 404                 #if defined(__cplusplus)
 405                         }
 406                 #endif
 407
 408 #endif
 409
 410 /** @} */
 411