Freescale Semiconductor FRDM-FXS-MULTI 데이터 시트

Sensors
Freescale Semiconductor, Inc.

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The transient detection function is similar to the freefall/motion detection function with the exception that a high-pass filter can be 
used to eliminate the DC offset from the acceleration data. There is an option to disable the high-pass filter, which causes the 
transient detection function to work in a similar manner to the motion detection function.

The transient detection function can be configured to signal an interrupt when the high-pass filtered acceleration delta values for 
any of the enabled axes exceeds the threshold programmed in TRANSIENT_THS for the debounce time programmed in 
TRANSIENT_COUNT. For more information on how to use and configure the transient detection function please refer to 
Freescale application note AN4461.

a_vecm_initz[13:8]

Most significant 6 bits of the signed 14-bit initial Z-axis value to be used as ref_z when A_VECM_CFG[a_vecm_initm] 
= 1. The resolution is determined by the settings made in XYZ_DATA_CFG[fs], and is equal to the accelerometer 
resolution.

a_vecm_initz[7:0]

0b0000_0000

a_vecm_initz[7:0]

LSB of the signed 14-bit initial Z-axis value to be used as ref_z when A_VECM_CFG[a_vecm_initm] = 1. The 
resolution is determined by the settings made in XYZ_DATA_CFG[fs], and is equal to the accelerometer resolution.

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—

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tran_ele

tran_zefe

tran_yefe

tran_xefe

tran_hpf_byp

0

0

0

0

0

0

0

0

tran_ele

Transient event flag latch enable. 
0: Event flag latch disabled: the transient interrupt flag reflects the real-time status of the function.
1: Event flag latch enabled:

 

the transient interrupt event flag is latched and a read of the TRANSIENT_SRC register is 

required to clear the event flag.

tran_zefe

Z-axis transient event flag enable. 
0: Z-axis event detection disabled
1: Z-axis event detection enabled. Raise event flag on Z-axis acceleration value greater than threshold.

tran_yefe

Y-axis transient event flag enable. 
0: Y-axis event detection disabled
1: Y-axis event detection enabled. Raise event flag on Y-axis acceleration value greater than threshold.

 tran_xefe

X-axis transient event flag enable. 
0: X-axis event detection disabled
1: X-axis event detection enabled. Raise event flag on X-axis acceleration value greater than threshold.

 tran_hpf_byp

Transient function high-pass filter bypass. 
0: High-pass filter is applied to accelerometer data input to the transient function. 
1: High-pass filter is not applied to accelerometer data input to the transient function.