Bosch SMB365 Application Note page 39

•
Select any acceleration range [21]
•
Select independent interrupt mode [22]
•
Put in Hysteresis and Threshold digits for X, Y and Z axis [23]
•
Start data acquisition [8]
•
accelerate, roll or tilt the TriBox board while watching the interrupt LED [25]
For Interrupt operation as a function of Threshold and Hysteresis the same as shown in chapter
4.3.2 before applies with one exception. Threshold and Hysteresis can be selected individually
for each axis. For Hysteresis set = Zero, the following logic applies, e.g.:
LED [25] = 1 if LSB
LED [25] = 0 if LSB
For Hysteresis set ≠ Zero, the following logic applies, e.g.:
LED [25] = 1 if LSB
LED [25] = 0 if LSB
The following example shows how to set up the axis specific Threshold and Hysteresis. The
calculation corresponds to the low g operation mode:
=
20 d
Threshold:
=
1 d 320
Hysteresis:
If Hysteresis is equal or above Threshold (LSB values), the interrupt functionality will be
disabled. For a total reset of the sensor internal interrupt information just switch to standby
mode [20] and continue.
Rev. 1.0
© Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such
copying and passing onto third parties.
.
7211RB11
Application Note
BlueBox Demo-Board for the digital sensors
SMB365 (acceleration) and SMD500 (pressure)
> Threshold OR LSB
X X
< Threshold AND LSB
X X
> Threshold OR LSB
X X
< Hysteresis AND LSB
X X
⋅ =
20 16 LSB 320 LSB
− ⋅ =
LSB 1 64 LSB
> Threshold
Y
< Threshold
Y
> Threshold
Y
< Hysteresis
Y
∝
20
∝
256 LSB . 1 28
Page 39
Bosch Sensortec
AN18002
OR LSB > Threshold
Y Z
AND LSB < Threshold
Y Z
OR LSB > Threshold
Y Z
AND LSB < Hysteresis
Y Z
⋅ =
64 mg . 1 28 g
− ⋅ =
g 1 256 mg . 1 02
Z
Z
Z
Z
g