1 CMA3000-D0x Accelerometer 1 CMA3000-D0x Accelerometer
2 ========================= 2 =========================
3 3
4 Supported chips: 4 Supported chips:
5 * VTI CMA3000-D0x 5 * VTI CMA3000-D0x
6 6
7 Datasheet: 7 Datasheet:
8 CMA3000-D0X Product Family Specification 828 8 CMA3000-D0X Product Family Specification 8281000A.02.pdf
9 <http://www.vti.fi/en/> 9 <http://www.vti.fi/en/>
10 10
11 :Author: Hemanth V <hemanthv@ti.com> 11 :Author: Hemanth V <hemanthv@ti.com>
12 12
13 13
14 Description 14 Description
15 ----------- 15 -----------
16 16
17 CMA3000 Tri-axis accelerometer supports Motion 17 CMA3000 Tri-axis accelerometer supports Motion detect, Measurement and
18 Free fall modes. 18 Free fall modes.
19 19
20 Motion Detect Mode: 20 Motion Detect Mode:
21 Its the low power mode where interrupts ar 21 Its the low power mode where interrupts are generated only
22 when motion exceeds the defined thresholds 22 when motion exceeds the defined thresholds.
23 23
24 Measurement Mode: 24 Measurement Mode:
25 This mode is used to read the acceleration 25 This mode is used to read the acceleration data on X,Y,Z
26 axis and supports 400, 100, 40 Hz sample f 26 axis and supports 400, 100, 40 Hz sample frequency.
27 27
28 Free fall Mode: 28 Free fall Mode:
29 This mode is intended to save system resou 29 This mode is intended to save system resources.
30 30
31 Threshold values: 31 Threshold values:
32 Chip supports defining threshold values fo 32 Chip supports defining threshold values for above modes
33 which includes time and g value. Refer pro 33 which includes time and g value. Refer product specifications for
34 more details. 34 more details.
35 35
36 CMA3000 chip supports mutually exclusive I2C a 36 CMA3000 chip supports mutually exclusive I2C and SPI interfaces for
37 communication, currently the driver supports I 37 communication, currently the driver supports I2C based communication only.
38 Initial configuration for bus mode is set in n 38 Initial configuration for bus mode is set in non volatile memory and can later
39 be modified through bus interface command. 39 be modified through bus interface command.
40 40
41 Driver reports acceleration data through input 41 Driver reports acceleration data through input subsystem. It generates ABS_MISC
42 event with value 1 when free fall is detected. 42 event with value 1 when free fall is detected.
43 43
44 Platform data need to be configured for initia 44 Platform data need to be configured for initial default values.
45 45
46 Platform Data 46 Platform Data
47 ------------- 47 -------------
48 48
49 fuzz_x: 49 fuzz_x:
50 Noise on X Axis 50 Noise on X Axis
51 51
52 fuzz_y: 52 fuzz_y:
53 Noise on Y Axis 53 Noise on Y Axis
54 54
55 fuzz_z: 55 fuzz_z:
56 Noise on Z Axis 56 Noise on Z Axis
57 57
58 g_range: 58 g_range:
59 G range in milli g i.e 2000 or 8000 59 G range in milli g i.e 2000 or 8000
60 60
61 mode: 61 mode:
62 Default Operating mode 62 Default Operating mode
63 63
64 mdthr: 64 mdthr:
65 Motion detect g range threshold value 65 Motion detect g range threshold value
66 66
67 mdfftmr: 67 mdfftmr:
68 Motion detect and free fall time threshold 68 Motion detect and free fall time threshold value
69 69
70 ffthr: 70 ffthr:
71 Free fall g range threshold value 71 Free fall g range threshold value
72 72
73 Input Interface 73 Input Interface
74 --------------- 74 ---------------
75 75
76 Input driver version is 1.0.0 76 Input driver version is 1.0.0
77 Input device ID: bus 0x18 vendor 0x0 product 0 77 Input device ID: bus 0x18 vendor 0x0 product 0x0 version 0x0
78 Input device name: "cma3000-accelerometer" 78 Input device name: "cma3000-accelerometer"
79 79
80 Supported events:: 80 Supported events::
81 81
82 Event type 0 (Sync) 82 Event type 0 (Sync)
83 Event type 3 (Absolute) 83 Event type 3 (Absolute)
84 Event code 0 (X) 84 Event code 0 (X)
85 Value 47 85 Value 47
86 Min -8000 86 Min -8000
87 Max 8000 87 Max 8000
88 Fuzz 200 88 Fuzz 200
89 Event code 1 (Y) 89 Event code 1 (Y)
90 Value -28 90 Value -28
91 Min -8000 91 Min -8000
92 Max 8000 92 Max 8000
93 Fuzz 200 93 Fuzz 200
94 Event code 2 (Z) 94 Event code 2 (Z)
95 Value 905 95 Value 905
96 Min -8000 96 Min -8000
97 Max 8000 97 Max 8000
98 Fuzz 200 98 Fuzz 200
99 Event code 40 (Misc) 99 Event code 40 (Misc)
100 Value 0 100 Value 0
101 Min 0 101 Min 0
102 Max 1 102 Max 1
103 Event type 4 (Misc) 103 Event type 4 (Misc)
104 104
105 105
106 Register/Platform parameters Description 106 Register/Platform parameters Description
107 ---------------------------------------- 107 ----------------------------------------
108 108
109 mode:: 109 mode::
110 110
111 0: power down mode 111 0: power down mode
112 1: 100 Hz Measurement mode 112 1: 100 Hz Measurement mode
113 2: 400 Hz Measurement mode 113 2: 400 Hz Measurement mode
114 3: 40 Hz Measurement mode 114 3: 40 Hz Measurement mode
115 4: Motion Detect mode (default) 115 4: Motion Detect mode (default)
116 5: 100 Hz Free fall mode 116 5: 100 Hz Free fall mode
117 6: 40 Hz Free fall mode 117 6: 40 Hz Free fall mode
118 7: Power off mode 118 7: Power off mode
119 119
120 grange:: 120 grange::
121 121
122 2000: 2000 mg or 2G Range 122 2000: 2000 mg or 2G Range
123 8000: 8000 mg or 8G Range 123 8000: 8000 mg or 8G Range
124 124
125 mdthr:: 125 mdthr::
126 126
127 X: X * 71mg (8G Range) 127 X: X * 71mg (8G Range)
128 X: X * 18mg (2G Range) 128 X: X * 18mg (2G Range)
129 129
130 mdfftmr:: 130 mdfftmr::
131 131
132 X: (X & 0x70) * 100 ms (MDTMR) 132 X: (X & 0x70) * 100 ms (MDTMR)
133 (X & 0x0F) * 2.5 ms (FFTMR 400 Hz) 133 (X & 0x0F) * 2.5 ms (FFTMR 400 Hz)
134 (X & 0x0F) * 10 ms (FFTMR 100 Hz) 134 (X & 0x0F) * 10 ms (FFTMR 100 Hz)
135 135
136 ffthr:: 136 ffthr::
137 137
138 X: (X >> 2) * 18mg (2G Range) 138 X: (X >> 2) * 18mg (2G Range)
139 X: (X & 0x0F) * 71 mg (8G Range) 139 X: (X & 0x0F) * 71 mg (8G Range)
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