Data Sheet
MMA8452Q
Sensors
24 Freescale Semiconductor, Inc.
0x11: Portrait/Landscape Configuration Register
This register enables the Portrait/Landscape function and sets the behavior of the debounce counter.
0x12: Portrait/Landscape Debounce Counter
This register sets the debounce count for the orientation state transition. The minimum debounce latency is determined by the
data rate set by the product of the selected system ODR and PL_COUNT registers. Any transition from WAKE to SLEEP or vice
versa resets the internal Landscape/Portrait debounce counter. Note: The debounce counter weighting (time step) changes
based on the ODR and the Oversampling mode. Table 22 explains the time step value for all sample rates and all Oversampling
modes.
0x13: PL_BF_ZCOMP Back/Front and Z Compensation Register
The Z-Lock angle compensation is set to 29°. The Back to Front trip angle is set to ±75°.
Note: All angles are accurate to ±2°.
0x11: PL_CFG Register (Read/Write)
Bit
7
Bit
6
Bit
5
Bit
4
Bit
3
Bit
2
Bit
1
Bit
0
DBCNTM PL_EN 0 0 0 0 0 0
Table 20. PL_CFG Description
DBCNTM
Debounce counter mode selection. Default value: 1
0: Decrements debounce whenever condition of interest is no longer valid.
1: Clears counter whenever condition of interest is no longer valid.
PL_EN
Portrait/Landscape Detection Enable. Default value: 0
0: Portrait/Landscape Detection is Disabled.
1: Portrait/Landscape Detection is Enabled.
0x12: PL_COUNT Register (Read/Write)
Bit
7
Bit
6
Bit
5
Bit
4
Bit
3
Bit
2
Bit
1
Bit
0
DBNCE[7] DBNCE[6] DBNCE[5] DBNCE[4] DBNCE[3] DBNCE[2] DBNCE[1] DBNCE[0]
Table 21.
PL_COUNT Description
DBCNE[7:0]
Debounce Count value. Default value: 0000_0000.
Table 22. PL_COUNT Relationship with the ODR
ODR (Hz)
Max Time Range (s) Time Step (ms)
Normal LPLN HighRes LP Normal LPLN HighRes LP
800 0.319 0.319 0.319 0.319 1.25 1.25 1.25 1.25
400 0.638 0.638 0.638 0.638 2.5 2.5 2.5 2.5
200 1.28 1.28 0.638 1.28 5 5 2.5 5
100 2.55 2.55 0.638 2.55 10 10 2.5 10
50 5.1 5.1 0.638 5.1 20 20 2.5 20
12.5 5.1 20.4 0.638 20.4 20 80 2.5 80
6.25 5.1 20.4 0.638 40.8 20 80 2.5 160
1.56 5.1 20.4 0.638 40.8 20 80 2.5 160
0x13: PL_BF_ZCOMP Register (Read Only)
Bit
7
Bit
6
Bit
5
Bit 4 Bit
3
Bit
2
Bit
1
Bit
0
BKFR[1] BKFR[0] 0 0 0 ZLOCK[2] ZLOCK[1] ZLOCK[0]
Table 23. PL_BF_ZCOMP Description
BKFR[1:0]
Back Front Trip Angle Fixed Threshold = 01 which is
≥ ±75°.
ZLOCK[2:0]
Z-Lock Angle Fixed Threshold = 100 which is 29°.