Minor documentation cleanups.
[pub/USBasp.git] / 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 * ADC driver for the AT90USB1287, AT90USB1286, AT90USB647, AT90USB646, ATMEGA16U4 and ATMEGA32U4 AVRs.
35 *
36 * \note This file should not be included directly. It is automatically included as needed by the ADC driver
37 * dispatch header located in LUFA/Drivers/Peripheral/ADC.h.
38 */
39
40 /** \ingroup Group_ADC
41 * @defgroup Group_ADC_AVRU4U6U7 Series U4, U6 and U7 Model ADC Driver
42 *
43 * ADC driver for the AT90USB1287, AT90USB1286, AT90USB647, AT90USB646, ATMEGA16U4 and ATMEGA32U4 AVRs.
44 *
45 * \note This file should not be included directly. It is automatically included as needed by the ADC driver
46 * dispatch header located in LUFA/Drivers/Peripheral/ADC.h.
47 *
48 * @{
49 */
50
51 #ifndef __ADC_AVRU4U6U7_H__
52 #define __ADC_AVRU4U6U7_H__
53
54 /* Includes: */
55 #include "../../../Common/Common.h"
56
57 #include <avr/io.h>
58 #include <stdbool.h>
59
60 /* Enable C linkage for C++ Compilers: */
61 #if defined(__cplusplus)
62 extern "C" {
63 #endif
64
65 /* Preprocessor Checks: */
66 #if !defined(__INCLUDE_FROM_ADC_H)
67 #error Do not include this file directly. Include LUFA/Drivers/Peripheral/ADC.h instead.
68 #endif
69
70 /* Public Interface - May be used in end-application: */
71 /* Macros: */
72 /** Reference mask, for using the voltage present at the AVR's AREF pin for the ADC reference. */
73 #define ADC_REFERENCE_AREF 0
74
75 /** Reference mask, for using the voltage present at the AVR's AVCC pin for the ADC reference. */
76 #define ADC_REFERENCE_AVCC (1 << REFS0)
77
78 /** Reference mask, for using the internally generated 2.56V reference voltage as the ADC reference. */
79 #define ADC_REFERENCE_INT2560MV ((1 << REFS1)| (1 << REFS0))
80
81 /** Left-adjusts the 10-bit ADC result, so that the upper 8 bits of the value returned by the
82 * ADC_GetResult() macro contain the 8 most significant bits of the result. */
83 #define ADC_LEFT_ADJUSTED (1 << ADLAR)
84
85 /** Right-adjusts the 10-bit ADC result, so that the lower 8 bits of the value returned by the
86 * ADC_GetResult() macro contain the 8 least significant bits of the result. */
87 #define ADC_RIGHT_ADJUSTED (0 << ADLAR)
88
89 /** Sets the ADC mode to free running, so that conversions take place continuously as fast as the ADC
90 * is capable of at the given input clock speed. */
91 #define ADC_FREE_RUNNING (1 << ADATE)
92
93 /** Sets the ADC mode to single conversion, so that only a single conversion will take place before
94 * the ADC returns to idle. */
95 #define ADC_SINGLE_CONVERSION (0 << ADATE)
96
97 /** Sets the ADC input clock to prescale by a factor of 2 the AVR's system clock. */
98 #define ADC_PRESCALE_2 (1 << ADPS0)
99
100 /** Sets the ADC input clock to prescale by a factor of 4 the AVR's system clock. */
101 #define ADC_PRESCALE_4 (1 << ADPS1)
102
103 /** Sets the ADC input clock to prescale by a factor of 8 the AVR's system clock. */
104 #define ADC_PRESCALE_8 ((1 << ADPS0) | (1 << ADPS1))
105
106 /** Sets the ADC input clock to prescale by a factor of 16 the AVR's system clock. */
107 #define ADC_PRESCALE_16 (1 << ADPS2)
108
109 /** Sets the ADC input clock to prescale by a factor of 32 the AVR's system clock. */
110 #define ADC_PRESCALE_32 ((1 << ADPS2) | (1 << ADPS0))
111
112 /** Sets the ADC input clock to prescale by a factor of 64 the AVR's system clock. */
113 #define ADC_PRESCALE_64 ((1 << ADPS2) | (1 << ADPS1))
114
115 /** Sets the ADC input clock to prescale by a factor of 128 the AVR's system clock. */
116 #define ADC_PRESCALE_128 ((1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0))
117
118 //@{
119 /** MUX mask define for the ADC0 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
120 #define ADC_CHANNEL0 (0x00 << MUX0)
121
122 /** MUX mask define for the ADC1 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
123 #define ADC_CHANNEL1 (0x01 << MUX0)
124
125 #if !(defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__))
126 /** MUX mask define for the ADC2 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
127 *
128 * \note Not available on all AVR models.
129 */
130 #define ADC_CHANNEL2 (0x02 << MUX0)
131
132 /** MUX mask define for the ADC3 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
133 *
134 * \note Not available on all AVR models.
135 */
136 #define ADC_CHANNEL3 (0x03 << MUX0)
137 #endif
138
139 /** MUX mask define for the ADC4 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
140 #define ADC_CHANNEL4 (0x04 << MUX0)
141
142 /** MUX mask define for the ADC5 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
143 #define ADC_CHANNEL5 (0x05 << MUX0)
144
145 /** MUX mask define for the ADC6 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
146 #define ADC_CHANNEL6 (0x06 << MUX0)
147
148 /** MUX mask define for the ADC7 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
149 #define ADC_CHANNEL7 (0x07 << MUX0)
150
151 /** MUX mask define for the internal 1.1V bandgap channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading. */
152 #define ADC_1100MV_BANDGAP (0x1E << MUX0)
153
154 #if (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__))
155 /** MUX mask define for the ADC8 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
156 *
157 * \note Not available on all AVR models.
158 */
159 #define ADC_CHANNEL8 ((1 << 8) | (0x00 << MUX0))
160
161 /** MUX mask define for the ADC9 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
162 *
163 * \note Not available on all AVR models.
164 */
165 #define ADC_CHANNEL9 ((1 << 8) | (0x01 << MUX0))
166
167 /** MUX mask define for the ADC10 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
168 *
169 * \note Not available on all AVR models.
170 */
171 #define ADC_CHANNEL10 ((1 << 8) | (0x02 << MUX0))
172
173 /** MUX mask define for the ADC11 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
174 *
175 * \note Not available on all AVR models.
176 */
177 #define ADC_CHANNEL11 ((1 << 8) | (0x03 << MUX0))
178
179 /** MUX mask define for the ADC12 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
180 *
181 * \note Not available on all AVR models.
182 */
183 #define ADC_CHANNEL12 ((1 << 8) | (0x04 << MUX0))
184
185 /** MUX mask define for the ADC13 channel of the ADC. See \ref ADC_StartReading and \ref ADC_GetChannelReading.
186 *
187 * \note Not available on all AVR models.
188 */
189 #define ADC_CHANNEL13 ((1 << 8) | (0x05 << MUX0))
190
191 /** MUX mask define for the internal temperature sensor channel of the ADC. See \ref ADC_StartReading and
192 * \ref ADC_GetChannelReading.
193 *
194 * \note Not available on all AVR models.
195 */
196 #define ADC_INT_TEMP_SENS ((1 << 8) | (0x07 << MUX0))
197 #endif
198 //@}
199
200 /* Pseudo-Function Macros: */
201 #if defined(__DOXYGEN__)
202 /** Initializes the ADC, ready for conversions. This must be called before any other ADC operations.
203 * The "mode" parameter should be a mask comprised of a conversion mode (free running or single) and
204 * prescaler masks.
205 *
206 * \param[in] Mode Mask of ADC settings, including adjustment, prescale, mode and reference
207 */
208 static inline void ADC_Init(uint8_t Mode);
209
210 /** Turns off the ADC. If this is called, any further ADC operations will require a call to
211 * \ref ADC_Init() before the ADC can be used again.
212 */
213 static inline void ADC_ShutDown(void);
214
215 /** Indicates if the ADC is currently enabled.
216 *
217 * \return Boolean true if the ADC subsystem is currently enabled, false otherwise.
218 */
219 static inline bool ADC_GetStatus(void);
220
221 /** Indicates if the current ADC conversion is completed, or still in progress.
222 *
223 * \return Boolean false if the reading is still taking place, or true if the conversion is
224 * complete and ready to be read out with \ref ADC_GetResult()
225 */
226 static inline bool ADC_IsReadingComplete(void);
227
228 /** Retrieves the conversion value of the last completed ADC conversion and clears the reading
229 * completion flag.
230 *
231 * \return The result of the last ADC conversion
232 */
233 static inline uint16_t ADC_GetResult(void);
234 #else
235 #define ADC_Init(mode) MACROS{ ADCSRA = ((1 << ADEN) | mode); }MACROE
236
237 #define ADC_ShutDown() MACROS{ ADCSRA = 0; }MACROE
238
239 #define ADC_GetStatus() ((ADCSRA & (1 << ADEN)) ? true : false)
240
241 #define ADC_IsReadingComplete() ((ADCSRA & (1 << ADIF)) ? true : false)
242
243 #define ADC_GetResult() (ADCSRA |= (1 << ADIF), ADC)
244 #endif
245
246 /* Inline Functions: */
247 /** Configures the given ADC channel, ready for ADC conversions. This function sets the
248 * associated port pin as an input and disables the digital portion of the I/O to reduce
249 * power consumption.
250 *
251 * \note This must only be called for ADC channels with are connected to a physical port
252 * pin of the AVR, denoted by its special alternative function ADCx.
253 * \n\n
254 *
255 * \note The channel number must be specified as an integer, and NOT a ADC_CHANNELx mask.
256 *
257 * \param[in] Channel ADC channel number to set up for conversions
258 */
259 static inline void ADC_SetupChannel(const uint8_t Channel)
260 {
261 #if (defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB646__) || \
262 defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB647__) || \
263 defined(__AVR_ATmega32U6__))
264 DDRF &= ~(1 << Channel);
265 DIDR0 |= (1 << Channel);
266 #elif (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
267 if (Channel < 8)
268 {
269 DDRF &= ~(1 << Channel);
270 DIDR0 |= (1 << Channel);
271 }
272 else if (Channel == 8)
273 {
274 DDRD &= ~(1 << 4);
275 DIDR2 |= (1 << 0);
276 }
277 else if (Channel < 11)
278 {
279 DDRD &= ~(1 << (Channel - 3));
280 DIDR2 |= (1 << (Channel - 8));
281 }
282 else
283 {
284 DDRB &= ~(1 << (Channel - 7));
285 DIDR2 |= (1 << (Channel - 8));
286 }
287 #endif
288 }
289
290 /** Deconfigures the given ADC channel, re-enabling digital I/O mode instead of analog. This
291 * function sets the associated port pin as an input and re-enabled the digital portion of
292 * the I/O.
293 *
294 * \note This must only be called for ADC channels with are connected to a physical port
295 * pin of the AVR, denoted by its special alternative function ADCx.
296 * \n\n
297 *
298 * \note The channel number must be specified as an integer, and NOT a ADC_CHANNELx mask.
299 *
300 * \param[in] Channel ADC channel number to set up for conversions
301 */
302 static inline void ADC_DisableChannel(const uint8_t Channel)
303 {
304 #if (defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB646__) || \
305 defined(__AVR_AT90USB1287__) || defined(__AVR_AT90USB647__) || \
306 defined(__AVR_ATmega32U6__))
307 DDRF &= ~(1 << Channel);
308 DIDR0 &= ~(1 << Channel);
309 #elif (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
310 if (Channel < 8)
311 {
312 DDRF &= ~(1 << Channel);
313 DIDR0 &= ~(1 << Channel);
314 }
315 else if (Channel == 8)
316 {
317 DDRD &= ~(1 << 4);
318 DIDR2 &= ~(1 << 0);
319 }
320 else if (Channel < 11)
321 {
322 DDRD &= ~(1 << (Channel - 3));
323 DIDR2 &= ~(1 << (Channel - 8));
324 }
325 else
326 {
327 DDRB &= ~(1 << (Channel - 7));
328 DIDR2 &= ~(1 << (Channel - 8));
329 }
330 #endif
331 }
332
333 /** Starts the reading of the given channel, but does not wait until the conversion has completed.
334 * Once executed, the conversion status can be determined via the \ref ADC_IsReadingComplete() macro and
335 * the result read via the \ref ADC_GetResult() macro.
336 *
337 * If the ADC has been initialized in free running mode, calling this function once will begin the repeated
338 * conversions. If the ADC is in single conversion mode (or the channel to convert from is to be changed),
339 * this function must be called each time a conversion is to take place.
340 *
341 * \param[in] MUXMask Mask comprising of an ADC channel mask, reference mask and adjustment mask
342 */
343 static inline void ADC_StartReading(const uint16_t MUXMask)
344 {
345 ADMUX = MUXMask;
346
347 #if (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__DOXYGEN__))
348 if (MUXMask & (1 << 8))
349 ADCSRB |= (1 << MUX5);
350 else
351 ADCSRB &= ~(1 << MUX5);
352 #endif
353
354 ADCSRA |= (1 << ADSC);
355 }
356
357 /** Performs a complete single reading from channel, including a polling spin-loop to wait for the
358 * conversion to complete, and the returning of the converted value.
359 *
360 * \note For free running mode, the automated conversions should be initialized with a single call
361 * to \ref ADC_StartReading() to select the channel and begin the automated conversions, and
362 * the results read directly from the \ref ADC_GetResult() instead to reduce overhead.
363 *
364 * \param[in] MUXMask Mask comprising of an ADC channel mask, reference mask and adjustment mask
365 */
366 static inline uint16_t ADC_GetChannelReading(const uint16_t MUXMask) ATTR_WARN_UNUSED_RESULT;
367 static inline uint16_t ADC_GetChannelReading(const uint16_t MUXMask)
368 {
369 ADC_StartReading(MUXMask);
370
371 while (!(ADC_IsReadingComplete()));
372
373 return ADC_GetResult();
374 }
375
376 /* Disable C linkage for C++ Compilers: */
377 #if defined(__cplusplus)
378 }
379 #endif
380
381 #endif
382
383 /** @} */