forked from boschsensortec/BME280_SensorAPI
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathbme280.c
1496 lines (1318 loc) · 49.3 KB
/
bme280.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/**
* Copyright (c) 2020 Bosch Sensortec GmbH. All rights reserved.
*
* BSD-3-Clause
*
* 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. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS 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.
*
* @file bme280.c
* @date 2020-01-24
* @version v3.4.3
*
*/
/*! @file bme280.c
* @brief Sensor driver for BME280 sensor
*/
#include "bme280.h"
/**\name Internal macros */
/* To identify osr settings selected by user */
#define OVERSAMPLING_SETTINGS UINT8_C(0x07)
/* To identify filter and standby settings selected by user */
#define FILTER_STANDBY_SETTINGS UINT8_C(0x18)
/*!
* @brief This internal API puts the device to sleep mode.
*
* @param[in] dev : Structure instance of bme280_dev.
*
* @return Result of API execution status.
* @retval zero -> Success / +ve value -> Warning / -ve value -> Error
*/
static int8_t put_device_to_sleep(const struct bme280_dev *dev);
/*!
* @brief This internal API writes the power mode in the sensor.
*
* @param[in] dev : Structure instance of bme280_dev.
* @param[in] sensor_mode : Variable which contains the power mode to be set.
*
* @return Result of API execution status.
* @retval zero -> Success / +ve value -> Warning / -ve value -> Error
*/
static int8_t write_power_mode(uint8_t sensor_mode, const struct bme280_dev *dev);
/*!
* @brief This internal API is used to validate the device pointer for
* null conditions.
*
* @param[in] dev : Structure instance of bme280_dev.
*
* @return Result of API execution status
* @retval zero -> Success / +ve value -> Warning / -ve value -> Error
*/
static int8_t null_ptr_check(const struct bme280_dev *dev);
/*!
* @brief This internal API interleaves the register address between the
* register data buffer for burst write operation.
*
* @param[in] reg_addr : Contains the register address array.
* @param[out] temp_buff : Contains the temporary buffer to store the
* register data and register address.
* @param[in] reg_data : Contains the register data to be written in the
* temporary buffer.
* @param[in] len : No of bytes of data to be written for burst write.
*/
static void interleave_reg_addr(const uint8_t *reg_addr, uint8_t *temp_buff, const uint8_t *reg_data, uint8_t len);
/*!
* @brief This internal API reads the calibration data from the sensor, parse
* it and store in the device structure.
*
* @param[in] dev : Structure instance of bme280_dev.
*
* @return Result of API execution status
* @retval zero -> Success / +ve value -> Warning / -ve value -> Error
*/
static int8_t get_calib_data(struct bme280_dev *dev);
/*!
* @brief This internal API is used to parse the temperature and
* pressure calibration data and store it in the device structure.
*
* @param[out] dev : Structure instance of bme280_dev to store the calib data.
* @param[in] reg_data : Contains the calibration data to be parsed.
*/
static void parse_temp_press_calib_data(const uint8_t *reg_data, struct bme280_dev *dev);
/*!
* @brief This internal API is used to parse the humidity calibration data
* and store it in device structure.
*
* @param[out] dev : Structure instance of bme280_dev to store the calib data.
* @param[in] reg_data : Contains calibration data to be parsed.
*/
static void parse_humidity_calib_data(const uint8_t *reg_data, struct bme280_dev *dev);
#ifdef BME280_FLOAT_ENABLE
/*!
* @brief This internal API is used to compensate the raw pressure data and
* return the compensated pressure data in double data type.
*
* @param[in] uncomp_data : Contains the uncompensated pressure data.
* @param[in] calib_data : Pointer to the calibration data structure.
*
* @return Compensated pressure data.
* @retval Compensated pressure data in double.
*/
static double compensate_pressure(const struct bme280_uncomp_data *uncomp_data,
const struct bme280_calib_data *calib_data);
/*!
* @brief This internal API is used to compensate the raw humidity data and
* return the compensated humidity data in double data type.
*
* @param[in] uncomp_data : Contains the uncompensated humidity data.
* @param[in] calib_data : Pointer to the calibration data structure.
*
* @return Compensated humidity data.
* @retval Compensated humidity data in double.
*/
static double compensate_humidity(const struct bme280_uncomp_data *uncomp_data,
const struct bme280_calib_data *calib_data);
/*!
* @brief This internal API is used to compensate the raw temperature data and
* return the compensated temperature data in double data type.
*
* @param[in] uncomp_data : Contains the uncompensated temperature data.
* @param[in] calib_data : Pointer to calibration data structure.
*
* @return Compensated temperature data.
* @retval Compensated temperature data in double.
*/
static double compensate_temperature(const struct bme280_uncomp_data *uncomp_data,
struct bme280_calib_data *calib_data);
#else
/*!
* @brief This internal API is used to compensate the raw temperature data and
* return the compensated temperature data in integer data type.
*
* @param[in] uncomp_data : Contains the uncompensated temperature data.
* @param[in] calib_data : Pointer to calibration data structure.
*
* @return Compensated temperature data.
* @retval Compensated temperature data in integer.
*/
static int32_t compensate_temperature(const struct bme280_uncomp_data *uncomp_data,
struct bme280_calib_data *calib_data);
/*!
* @brief This internal API is used to compensate the raw pressure data and
* return the compensated pressure data in integer data type.
*
* @param[in] uncomp_data : Contains the uncompensated pressure data.
* @param[in] calib_data : Pointer to the calibration data structure.
*
* @return Compensated pressure data.
* @retval Compensated pressure data in integer.
*/
static uint32_t compensate_pressure(const struct bme280_uncomp_data *uncomp_data,
const struct bme280_calib_data *calib_data);
/*!
* @brief This internal API is used to compensate the raw humidity data and
* return the compensated humidity data in integer data type.
*
* @param[in] uncomp_data : Contains the uncompensated humidity data.
* @param[in] calib_data : Pointer to the calibration data structure.
*
* @return Compensated humidity data.
* @retval Compensated humidity data in integer.
*/
static uint32_t compensate_humidity(const struct bme280_uncomp_data *uncomp_data,
const struct bme280_calib_data *calib_data);
#endif
/*!
* @brief This internal API is used to identify the settings which the user
* wants to modify in the sensor.
*
* @param[in] sub_settings : Contains the settings subset to identify particular
* group of settings which the user is interested to change.
* @param[in] desired_settings : Contains the user specified settings.
*
* @return Indicates whether user is interested to modify the settings which
* are related to sub_settings.
* @retval True -> User wants to modify this group of settings
* @retval False -> User does not want to modify this group of settings
*/
static uint8_t are_settings_changed(uint8_t sub_settings, uint8_t desired_settings);
/*!
* @brief This API sets the humidity oversampling settings of the sensor.
*
* @param[in] dev : Structure instance of bme280_dev.
*
* @return Result of API execution status
* @retval zero -> Success / +ve value -> Warning / -ve value -> Error
*/
static int8_t set_osr_humidity_settings(const struct bme280_settings *settings, const struct bme280_dev *dev);
/*!
* @brief This internal API sets the oversampling settings for pressure,
* temperature and humidity in the sensor.
*
* @param[in] desired_settings : Variable used to select the settings which
* are to be set.
* @param[in] dev : Structure instance of bme280_dev.
*
* @return Result of API execution status
* @retval zero -> Success / +ve value -> Warning / -ve value -> Error
*/
static int8_t set_osr_settings(uint8_t desired_settings,
const struct bme280_settings *settings,
const struct bme280_dev *dev);
/*!
* @brief This API sets the pressure and/or temperature oversampling settings
* in the sensor according to the settings selected by the user.
*
* @param[in] dev : Structure instance of bme280_dev.
* @param[in] desired_settings: variable to select the pressure and/or
* temperature oversampling settings.
*
* @return Result of API execution status
* @retval zero -> Success / +ve value -> Warning / -ve value -> Error
*/
static int8_t set_osr_press_temp_settings(uint8_t desired_settings,
const struct bme280_settings *settings,
const struct bme280_dev *dev);
/*!
* @brief This internal API fills the pressure oversampling settings provided by
* the user in the data buffer so as to write in the sensor.
*
* @param[in] dev : Structure instance of bme280_dev.
* @param[out] reg_data : Variable which is filled according to the pressure
* oversampling data provided by the user.
*/
static void fill_osr_press_settings(uint8_t *reg_data, const struct bme280_settings *settings);
/*!
* @brief This internal API fills the temperature oversampling settings provided
* by the user in the data buffer so as to write in the sensor.
*
* @param[in] dev : Structure instance of bme280_dev.
* @param[out] reg_data : Variable which is filled according to the temperature
* oversampling data provided by the user.
*/
static void fill_osr_temp_settings(uint8_t *reg_data, const struct bme280_settings *settings);
/*!
* @brief This internal API sets the filter and/or standby duration settings
* in the sensor according to the settings selected by the user.
*
* @param[in] dev : Structure instance of bme280_dev.
* @param[in] desired_settings : variable to select the filter and/or
* standby duration settings.
*
* @return Result of API execution status
* @retval zero -> Success / +ve value -> Warning / -ve value -> Error
*/
static int8_t set_filter_standby_settings(uint8_t desired_settings,
const struct bme280_settings *settings,
const struct bme280_dev *dev);
/*!
* @brief This internal API fills the filter settings provided by the user
* in the data buffer so as to write in the sensor.
*
* @param[in] dev : Structure instance of bme280_dev.
* @param[out] reg_data : Variable which is filled according to the filter
* settings data provided by the user.
*/
static void fill_filter_settings(uint8_t *reg_data, const struct bme280_settings *settings);
/*!
* @brief This internal API fills the standby duration settings provided by the
* user in the data buffer so as to write in the sensor.
*
* @param[in] dev : Structure instance of bme280_dev.
* @param[out] reg_data : Variable which is filled according to the standby
* settings data provided by the user.
*/
static void fill_standby_settings(uint8_t *reg_data, const struct bme280_settings *settings);
/*!
* @brief This internal API parse the oversampling(pressure, temperature
* and humidity), filter and standby duration settings and store in the
* device structure.
*
* @param[out] dev : Structure instance of bme280_dev.
* @param[in] reg_data : Register data to be parsed.
*/
static void parse_device_settings(const uint8_t *reg_data, struct bme280_settings *settings);
/*!
* @brief This internal API reloads the already existing device settings in the
* sensor after soft reset.
*
* @param[in] dev : Structure instance of bme280_dev.
* @param[in] settings : Pointer variable which contains the settings to
* be set in the sensor.
*
* @return Result of API execution status
* @retval zero -> Success / +ve value -> Warning / -ve value -> Error
*/
static int8_t reload_device_settings(const struct bme280_settings *settings, const struct bme280_dev *dev);
/****************** Global Function Definitions *******************************/
/*!
* @brief This API is the entry point.
* It reads the chip-id and calibration data from the sensor.
*/
int8_t bme280_init(struct bme280_dev *dev)
{
int8_t rslt;
/* chip id read try count */
uint8_t try_count = 5;
uint8_t chip_id = 0;
/* Check for null pointer in the device structure*/
rslt = null_ptr_check(dev);
/* Proceed if null check is fine */
if (rslt == BME280_OK)
{
while (try_count)
{
/* Read the chip-id of bme280 sensor */
rslt = bme280_get_regs(BME280_CHIP_ID_ADDR, &chip_id, 1, dev);
/* Check for chip id validity */
if ((rslt == BME280_OK) && (chip_id == BME280_CHIP_ID))
{
dev->chip_id = chip_id;
/* Reset the sensor */
rslt = bme280_soft_reset(dev);
if (rslt == BME280_OK)
{
/* Read the calibration data */
rslt = get_calib_data(dev);
}
break;
}
/* Wait for 1 ms */
dev->delay_ms(1);
--try_count;
}
/* Chip id check failed */
if (!try_count)
{
rslt = BME280_E_DEV_NOT_FOUND;
}
}
return rslt;
}
/*!
* @brief This API reads the data from the given register address of the sensor.
*/
int8_t bme280_get_regs(uint8_t reg_addr, uint8_t *reg_data, uint16_t len, const struct bme280_dev *dev)
{
int8_t rslt;
/* Check for null pointer in the device structure*/
rslt = null_ptr_check(dev);
/* Proceed if null check is fine */
if (rslt == BME280_OK)
{
/* If interface selected is SPI */
if (dev->intf != BME280_I2C_INTF)
{
reg_addr = reg_addr | 0x80;
}
/* Read the data */
rslt = dev->read(dev->dev_id, reg_addr, reg_data, len);
/* Check for communication error */
if (rslt != BME280_OK)
{
rslt = BME280_E_COMM_FAIL;
}
}
return rslt;
}
/*!
* @brief This API writes the given data to the register address
* of the sensor.
*/
int8_t bme280_set_regs(uint8_t *reg_addr, const uint8_t *reg_data, uint8_t len, const struct bme280_dev *dev)
{
int8_t rslt;
uint8_t temp_buff[20]; /* Typically not to write more than 10 registers */
if (len > 10)
{
len = 10;
}
uint16_t temp_len;
uint8_t reg_addr_cnt;
/* Check for null pointer in the device structure*/
rslt = null_ptr_check(dev);
/* Check for arguments validity */
if ((rslt == BME280_OK) && (reg_addr != NULL) && (reg_data != NULL))
{
if (len != 0)
{
temp_buff[0] = reg_data[0];
/* If interface selected is SPI */
if (dev->intf != BME280_I2C_INTF)
{
for (reg_addr_cnt = 0; reg_addr_cnt < len; reg_addr_cnt++)
{
reg_addr[reg_addr_cnt] = reg_addr[reg_addr_cnt] & 0x7F;
}
}
/* Burst write mode */
if (len > 1)
{
/* Interleave register address w.r.t data for
* burst write
*/
interleave_reg_addr(reg_addr, temp_buff, reg_data, len);
temp_len = ((len * 2) - 1);
}
else
{
temp_len = len;
}
rslt = dev->write(dev->dev_id, reg_addr[0], temp_buff, temp_len);
/* Check for communication error */
if (rslt != BME280_OK)
{
rslt = BME280_E_COMM_FAIL;
}
}
else
{
rslt = BME280_E_INVALID_LEN;
}
}
else
{
rslt = BME280_E_NULL_PTR;
}
return rslt;
}
/*!
* @brief This API sets the oversampling, filter and standby duration
* (normal mode) settings in the sensor.
*/
int8_t bme280_set_sensor_settings(uint8_t desired_settings, const struct bme280_dev *dev)
{
int8_t rslt;
uint8_t sensor_mode;
/* Check for null pointer in the device structure*/
rslt = null_ptr_check(dev);
/* Proceed if null check is fine */
if (rslt == BME280_OK)
{
rslt = bme280_get_sensor_mode(&sensor_mode, dev);
if ((rslt == BME280_OK) && (sensor_mode != BME280_SLEEP_MODE))
{
rslt = put_device_to_sleep(dev);
}
if (rslt == BME280_OK)
{
/* Check if user wants to change oversampling
* settings
*/
if (are_settings_changed(OVERSAMPLING_SETTINGS, desired_settings))
{
rslt = set_osr_settings(desired_settings, &dev->settings, dev);
}
/* Check if user wants to change filter and/or
* standby settings
*/
if ((rslt == BME280_OK) && are_settings_changed(FILTER_STANDBY_SETTINGS, desired_settings))
{
rslt = set_filter_standby_settings(desired_settings, &dev->settings, dev);
}
}
}
return rslt;
}
/*!
* @brief This API gets the oversampling, filter and standby duration
* (normal mode) settings from the sensor.
*/
int8_t bme280_get_sensor_settings(struct bme280_dev *dev)
{
int8_t rslt;
uint8_t reg_data[4];
/* Check for null pointer in the device structure*/
rslt = null_ptr_check(dev);
/* Proceed if null check is fine */
if (rslt == BME280_OK)
{
rslt = bme280_get_regs(BME280_CTRL_HUM_ADDR, reg_data, 4, dev);
if (rslt == BME280_OK)
{
parse_device_settings(reg_data, &dev->settings);
}
}
return rslt;
}
/*!
* @brief This API sets the power mode of the sensor.
*/
int8_t bme280_set_sensor_mode(uint8_t sensor_mode, const struct bme280_dev *dev)
{
int8_t rslt;
uint8_t last_set_mode;
/* Check for null pointer in the device structure*/
rslt = null_ptr_check(dev);
if (rslt == BME280_OK)
{
rslt = bme280_get_sensor_mode(&last_set_mode, dev);
/* If the sensor is not in sleep mode put the device to sleep
* mode
*/
if ((rslt == BME280_OK) && (last_set_mode != BME280_SLEEP_MODE))
{
rslt = put_device_to_sleep(dev);
}
/* Set the power mode */
if (rslt == BME280_OK)
{
rslt = write_power_mode(sensor_mode, dev);
}
}
return rslt;
}
/*!
* @brief This API gets the power mode of the sensor.
*/
int8_t bme280_get_sensor_mode(uint8_t *sensor_mode, const struct bme280_dev *dev)
{
int8_t rslt;
/* Check for null pointer in the device structure*/
rslt = null_ptr_check(dev);
if (rslt == BME280_OK)
{
/* Read the power mode register */
rslt = bme280_get_regs(BME280_PWR_CTRL_ADDR, sensor_mode, 1, dev);
/* Assign the power mode in the device structure */
*sensor_mode = BME280_GET_BITS_POS_0(*sensor_mode, BME280_SENSOR_MODE);
}
return rslt;
}
/*!
* @brief This API performs the soft reset of the sensor.
*/
int8_t bme280_soft_reset(const struct bme280_dev *dev)
{
int8_t rslt;
uint8_t reg_addr = BME280_RESET_ADDR;
uint8_t status_reg = 0;
uint8_t try_run = 5;
/* 0xB6 is the soft reset command */
uint8_t soft_rst_cmd = BME280_SOFT_RESET_COMMAND;
/* Check for null pointer in the device structure*/
rslt = null_ptr_check(dev);
/* Proceed if null check is fine */
if (rslt == BME280_OK)
{
/* Write the soft reset command in the sensor */
rslt = bme280_set_regs(®_addr, &soft_rst_cmd, 1, dev);
if (rslt == BME280_OK)
{
/* If NVM not copied yet, Wait for NVM to copy */
do
{
/* As per data sheet - Table 1, startup time is 2 ms. */
dev->delay_ms(2);
rslt = bme280_get_regs(BME280_STATUS_REG_ADDR, &status_reg, 1, dev);
} while ((rslt == BME280_OK) && (try_run--) && (status_reg & BME280_STATUS_IM_UPDATE));
if (status_reg & BME280_STATUS_IM_UPDATE)
{
rslt = BME280_E_NVM_COPY_FAILED;
}
}
}
return rslt;
}
/*!
* @brief This API reads the pressure, temperature and humidity data from the
* sensor, compensates the data and store it in the bme280_data structure
* instance passed by the user.
*/
int8_t bme280_get_sensor_data(uint8_t sensor_comp, struct bme280_data *comp_data, struct bme280_dev *dev)
{
int8_t rslt;
/* Array to store the pressure, temperature and humidity data read from
* the sensor
*/
uint8_t reg_data[BME280_P_T_H_DATA_LEN] = { 0 };
struct bme280_uncomp_data uncomp_data = { 0 };
/* Check for null pointer in the device structure*/
rslt = null_ptr_check(dev);
if ((rslt == BME280_OK) && (comp_data != NULL))
{
/* Read the pressure and temperature data from the sensor */
rslt = bme280_get_regs(BME280_DATA_ADDR, reg_data, BME280_P_T_H_DATA_LEN, dev);
if (rslt == BME280_OK)
{
/* Parse the read data from the sensor */
bme280_parse_sensor_data(reg_data, &uncomp_data);
/* Compensate the pressure and/or temperature and/or
* humidity data from the sensor
*/
rslt = bme280_compensate_data(sensor_comp, &uncomp_data, comp_data, &dev->calib_data);
}
}
else
{
rslt = BME280_E_NULL_PTR;
}
return rslt;
}
/*!
* @brief This API is used to parse the pressure, temperature and
* humidity data and store it in the bme280_uncomp_data structure instance.
*/
void bme280_parse_sensor_data(const uint8_t *reg_data, struct bme280_uncomp_data *uncomp_data)
{
/* Variables to store the sensor data */
uint32_t data_xlsb;
uint32_t data_lsb;
uint32_t data_msb;
/* Store the parsed register values for pressure data */
data_msb = (uint32_t)reg_data[0] << 12;
data_lsb = (uint32_t)reg_data[1] << 4;
data_xlsb = (uint32_t)reg_data[2] >> 4;
uncomp_data->pressure = data_msb | data_lsb | data_xlsb;
/* Store the parsed register values for temperature data */
data_msb = (uint32_t)reg_data[3] << 12;
data_lsb = (uint32_t)reg_data[4] << 4;
data_xlsb = (uint32_t)reg_data[5] >> 4;
uncomp_data->temperature = data_msb | data_lsb | data_xlsb;
/* Store the parsed register values for humidity data */
data_msb = (uint32_t)reg_data[6] << 8;
data_lsb = (uint32_t)reg_data[7];
uncomp_data->humidity = data_msb | data_lsb;
}
/*!
* @brief This API is used to compensate the pressure and/or
* temperature and/or humidity data according to the component selected
* by the user.
*/
int8_t bme280_compensate_data(uint8_t sensor_comp,
const struct bme280_uncomp_data *uncomp_data,
struct bme280_data *comp_data,
struct bme280_calib_data *calib_data)
{
int8_t rslt = BME280_OK;
if ((uncomp_data != NULL) && (comp_data != NULL) && (calib_data != NULL))
{
/* Initialize to zero */
comp_data->temperature = 0;
comp_data->pressure = 0;
comp_data->humidity = 0;
/* If pressure or temperature component is selected */
if (sensor_comp & (BME280_PRESS | BME280_TEMP | BME280_HUM))
{
/* Compensate the temperature data */
comp_data->temperature = compensate_temperature(uncomp_data, calib_data);
}
if (sensor_comp & BME280_PRESS)
{
/* Compensate the pressure data */
comp_data->pressure = compensate_pressure(uncomp_data, calib_data);
}
if (sensor_comp & BME280_HUM)
{
/* Compensate the humidity data */
comp_data->humidity = compensate_humidity(uncomp_data, calib_data);
}
}
else
{
rslt = BME280_E_NULL_PTR;
}
return rslt;
}
/*!
* @brief This API is used to calculate the maximum delay in milliseconds required for the
* temperature/pressure/humidity(which ever at enabled) measurement to complete.
*/
uint32_t bme280_cal_meas_delay(const struct bme280_settings *settings)
{
uint32_t max_delay;
uint8_t temp_osr;
uint8_t pres_osr;
uint8_t hum_osr;
/*Array to map OSR config register value to actual OSR */
uint8_t osr_sett_to_act_osr[] = { 0, 1, 2, 4, 8, 16 };
/* Mapping osr settings to the actual osr values e.g. 0b101 -> osr X16 */
if (settings->osr_t <= 5)
{
temp_osr = osr_sett_to_act_osr[settings->osr_t];
}
else
{
temp_osr = 16;
}
if (settings->osr_p <= 5)
{
pres_osr = osr_sett_to_act_osr[settings->osr_p];
}
else
{
pres_osr = 16;
}
if (settings->osr_h <= 5)
{
hum_osr = osr_sett_to_act_osr[settings->osr_h];
}
else
{
hum_osr = 16;
}
max_delay =
(uint32_t)((BME280_MEAS_OFFSET + (BME280_MEAS_DUR * temp_osr) +
((BME280_MEAS_DUR * pres_osr) + BME280_PRES_HUM_MEAS_OFFSET) +
((BME280_MEAS_DUR * hum_osr) + BME280_PRES_HUM_MEAS_OFFSET)) / BME280_MEAS_SCALING_FACTOR);
return max_delay;
}
/*!
* @brief This internal API sets the oversampling settings for pressure,
* temperature and humidity in the sensor.
*/
static int8_t set_osr_settings(uint8_t desired_settings,
const struct bme280_settings *settings,
const struct bme280_dev *dev)
{
int8_t rslt = BME280_W_INVALID_OSR_MACRO;
if (desired_settings & BME280_OSR_HUM_SEL)
{
rslt = set_osr_humidity_settings(settings, dev);
}
if (desired_settings & (BME280_OSR_PRESS_SEL | BME280_OSR_TEMP_SEL))
{
rslt = set_osr_press_temp_settings(desired_settings, settings, dev);
}
return rslt;
}
/*!
* @brief This API sets the humidity oversampling settings of the sensor.
*/
static int8_t set_osr_humidity_settings(const struct bme280_settings *settings, const struct bme280_dev *dev)
{
int8_t rslt;
uint8_t ctrl_hum;
uint8_t ctrl_meas;
uint8_t reg_addr = BME280_CTRL_HUM_ADDR;
ctrl_hum = settings->osr_h & BME280_CTRL_HUM_MSK;
/* Write the humidity control value in the register */
rslt = bme280_set_regs(®_addr, &ctrl_hum, 1, dev);
/* Humidity related changes will be only effective after a
* write operation to ctrl_meas register
*/
if (rslt == BME280_OK)
{
reg_addr = BME280_CTRL_MEAS_ADDR;
rslt = bme280_get_regs(reg_addr, &ctrl_meas, 1, dev);
if (rslt == BME280_OK)
{
rslt = bme280_set_regs(®_addr, &ctrl_meas, 1, dev);
}
}
return rslt;
}
/*!
* @brief This API sets the pressure and/or temperature oversampling settings
* in the sensor according to the settings selected by the user.
*/
static int8_t set_osr_press_temp_settings(uint8_t desired_settings,
const struct bme280_settings *settings,
const struct bme280_dev *dev)
{
int8_t rslt;
uint8_t reg_addr = BME280_CTRL_MEAS_ADDR;
uint8_t reg_data;
rslt = bme280_get_regs(reg_addr, ®_data, 1, dev);
if (rslt == BME280_OK)
{
if (desired_settings & BME280_OSR_PRESS_SEL)
{
fill_osr_press_settings(®_data, settings);
}
if (desired_settings & BME280_OSR_TEMP_SEL)
{
fill_osr_temp_settings(®_data, settings);
}
/* Write the oversampling settings in the register */
rslt = bme280_set_regs(®_addr, ®_data, 1, dev);
}
return rslt;
}
/*!
* @brief This internal API sets the filter and/or standby duration settings
* in the sensor according to the settings selected by the user.
*/
static int8_t set_filter_standby_settings(uint8_t desired_settings,
const struct bme280_settings *settings,
const struct bme280_dev *dev)
{
int8_t rslt;
uint8_t reg_addr = BME280_CONFIG_ADDR;
uint8_t reg_data;
rslt = bme280_get_regs(reg_addr, ®_data, 1, dev);
if (rslt == BME280_OK)
{
if (desired_settings & BME280_FILTER_SEL)
{
fill_filter_settings(®_data, settings);
}
if (desired_settings & BME280_STANDBY_SEL)
{
fill_standby_settings(®_data, settings);
}
/* Write the oversampling settings in the register */
rslt = bme280_set_regs(®_addr, ®_data, 1, dev);
}
return rslt;
}
/*!
* @brief This internal API fills the filter settings provided by the user
* in the data buffer so as to write in the sensor.
*/
static void fill_filter_settings(uint8_t *reg_data, const struct bme280_settings *settings)
{
*reg_data = BME280_SET_BITS(*reg_data, BME280_FILTER, settings->filter);
}
/*!
* @brief This internal API fills the standby duration settings provided by
* the user in the data buffer so as to write in the sensor.
*/
static void fill_standby_settings(uint8_t *reg_data, const struct bme280_settings *settings)
{
*reg_data = BME280_SET_BITS(*reg_data, BME280_STANDBY, settings->standby_time);
}
/*!
* @brief This internal API fills the pressure oversampling settings provided by
* the user in the data buffer so as to write in the sensor.
*/
static void fill_osr_press_settings(uint8_t *reg_data, const struct bme280_settings *settings)
{
*reg_data = BME280_SET_BITS(*reg_data, BME280_CTRL_PRESS, settings->osr_p);
}
/*!
* @brief This internal API fills the temperature oversampling settings
* provided by the user in the data buffer so as to write in the sensor.
*/
static void fill_osr_temp_settings(uint8_t *reg_data, const struct bme280_settings *settings)
{
*reg_data = BME280_SET_BITS(*reg_data, BME280_CTRL_TEMP, settings->osr_t);
}
/*!
* @brief This internal API parse the oversampling(pressure, temperature
* and humidity), filter and standby duration settings and store in the
* device structure.
*/
static void parse_device_settings(const uint8_t *reg_data, struct bme280_settings *settings)
{
settings->osr_h = BME280_GET_BITS_POS_0(reg_data[0], BME280_CTRL_HUM);
settings->osr_p = BME280_GET_BITS(reg_data[2], BME280_CTRL_PRESS);
settings->osr_t = BME280_GET_BITS(reg_data[2], BME280_CTRL_TEMP);
settings->filter = BME280_GET_BITS(reg_data[3], BME280_FILTER);
settings->standby_time = BME280_GET_BITS(reg_data[3], BME280_STANDBY);
}
/*!
* @brief This internal API writes the power mode in the sensor.
*/
static int8_t write_power_mode(uint8_t sensor_mode, const struct bme280_dev *dev)
{
int8_t rslt;
uint8_t reg_addr = BME280_PWR_CTRL_ADDR;
/* Variable to store the value read from power mode register */
uint8_t sensor_mode_reg_val;