BMA222 Bosch Sensortec, BMA222 Datasheet - Page 51

• Manufacturer Part Number: BMA222
• Description: 3-AXIS ACCELEROMETER DIGITAL SMD
• Manufacturer: Bosch Sensortec

Specifications of BMA222

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 828-1025-2

5.15 Offset compensation
Register (0x36) contains settings for the offset compensation in general, for fast offset
compensation, and for slow offset compensation. Writing ´1´to (0x36) offset_reset sets all offset
compensation registers (0x38 to 0x3D) to zero.
Default value of (0x36) offset_reset is ´0´.
(0x36) cal_trigger starts the fast compensation process for the specified axis. The settings for
(0x36) cal_trigger are ´00b´ (no axis selected), ´01b´ (x-axis), ´10b´ (y-axis), ´11b´ (z-axis). A
non-zero value is kept until the fast compensation procedure is finished. Default value of (0x36)
cal_trigger is ´00b´.
(0x36) cal_rdy indicates the state of the fast compensation. (0x36) cal_rdy is ´0´ when (0x36)
cal_trigger has a nonzero value, otherwise (0x36) cal_rdy is ´1´.
Writing ´1´ (´0´) to (0x36) hp_z_en enables (disables) slow offset compensation for the z-axis.
Writing ´1´ (´0´) to (0x36) hp_y_en enables (disables) slow offset compensation for the y-axis.
Writing ´1´ (´0´) to (0x36) hp_x_en enables (disables) slow offset compensation for the x-axis.
Default value for each of (0x36) hp_x_en, (0x36) hp_y_en, and (0x36) hp_x_en is ´0´,
respectively.
Register (0x37) contains settings for the offset compensation in general, and for slow offset
compensation. (0x37) offset_target_z sets the target value for the offset compensation of the z-
axis.
(0x37) offset_target_y sets the target value for the offset compensation of the y-axis.
(0x37) offset_target_x sets the target value for the offset compensation of the x-axis.
The settings for (0x37) offset_target_x, (0x37) offset_target_y, and (0x37) offset_target_z are
´00b´ (0 g), ´01b´ (+1 g), ´10b´ (-1 g), and ´11b´ (0 g). Default value of each of (0x37)
offset_target_x, (0x37) offset_target_y, and (0x37) offset_target_z is ´00b´, respectively.
(0x37) cut_off defines the number of samples for comparison by the slow offset compensation.
The settings for (0x37) cut_off are ´0´ (8 samples) and ´1´ (16 samples). The default value of
(0x37) cut_off is ´0´.
Rev. 1.0
© Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such
as copying and passing on to 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.
Table 63: Offset compensation, fast offset compensation, register (0x36)
Table 64: Offset compensation, slow offset compensation, register (0x37)
reserved
_reset
offset
Bit 7
Bit 7
offset_tar
get_z<1>
trigger<1
Bit 6
Bit 6
cal_
>
offset_tar
get_z<0>
trigger<0
Bit 5
Bit 5
cal_
>
get_y<1>
offset_tar
cal_rdy
Bit 4
Bit 4
Data sheet
BMA222
Page 51
offset_tar
get_y<0>
reserve
Bit 3
Bit 3
d
hp_z_en
offset_tar
get_x<1>
Bit 2
Bit 2
hp_y_en
offset_tar
get_x<0>
Bit 1
Bit 1
Bosch Sensortec
07 March 2011
hp_x_en
cut_off
Bit 0
Bit 0