BMA255 datasheet(32/119 Pages) BOSCH

32 / 119 page

BMA255

Data sheet

Page 32

BST-BMA255-DS004-05 | Revision 1.2 | August 2014

Bosch Sensortec

third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.

Note: Specifications within this document are subject to change without notice.

The parameters (0x2A) tap_shock and (0x2A) tap_quiet apply to both single tap and double tap

detection, while (0x2A) tap_dur applies to double tap detection only. Within the duration of

(0x2A) tap_shock any slope exceeding (0x2B) tap_th after the first event is ignored. Contrary to

this, within the duration of (0x2A) tap_quiet no slope exceeding (0x2B) tap_th must occur,

otherwise the first event will be cancelled.

4.7.6.1 Single tap detection

A single tap is detected and the single tap interrupt is generated after the combined durations of

(0x2A) tap_shock and (0x2A) tap_quiet, if the corresponding slope conditions are fulfilled. The

interrupt is cleared after a delay of 12.5 ms.

Do not map single-tap to any INT pin if you do not want to use it.

4.7.6.2 Double tap detection

A double tap interrupt is generated if an event fulfilling the conditions for a single tap occurs

within the set duration in (0x2A) tap_dur after the completion of the first tap event. The interrupt

is automatically cleared after a delay of 12.5 ms.

4.7.6.3 Selecting the timing of tap detection

For each of parameters (0x2A) tap_shock and (0x2A) tap_quiet two values are selectable. By

writing ´0´ (´1´) to bit (0x2A) tap_shock the duration of (0x2A) tap_shock is set to 50 ms (75

ms). By writing ´0´ (´1´) to bit (0x2A) tap_quiet the duration of (0x2A) tap_quiet is set to 30 ms

(20 ms).

The length of (0x2A) tap_dur can be selected by setting the (0x2A) tap_dur bits according to

Table 11:

Table 11: Selection of tap_dur

(0x2A)

tap_dur

length of tap_dur

000b

50 ms

001b

100 ms

010b

150 ms

011b

200 ms

100b

250 ms

101b

375 ms

110b

500 ms

111b

700 ms

BMA255 Datasheet(PDF) 32 Page - Bosch Sensortec GmbH

BMA255 Datasheet(HTML) 32 Page - Bosch Sensortec GmbH

Html Pages

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 ...More

Datasheet Download

Link URL