AN2381 datasheet(30/47 Pages) STMICROELECTRONICS

30 / 47 page

Registers Description

AN2381

30/47

XHIE (YHIE, ZHIE) set an interrupt event to occur when the measured acceleration data on

X (Y, Z) channel is higher than the threshold set in FF_WU_THS register.

XLIE (YLIE, ZLIE) set an interrupt event to occur when the measured acceleration data on X

(Y, Z) channel is lower than the threshold set in FF_WU_THS register.

The threshold module which is used by the system to detect any free-fall or inertial wake-up

event is defined by FF_WU_THS_H and FF_WU_THS_L registers and it is given by their

concatenation FF_WU_THS_H & FF_WU_THS_L. The threshold value is expressed over

16 bit as an unsigned number and X, (Y, Z) high is true when the unsigned acceleration

value of the X (Y, Z) channel is higher than FF_WU_THS_H & FF_WU_THS_L. Similarly, X,

(Y, Z) low is true when the unsigned acceleration value of the X (Y, Z) channel is lower than

FF_WU_THS_H & FF_WU_THS_L. Refer to Figure 12 for more details.

Figure 12.

FF_WU_CFG High and Low

5.4.3

FF_WU_SRC (31h)

Free-fall and wake-up source register. Read only register.

+ Full Scale

- Full Scale

0 g level

Threshold module

X (Y, Z) high

X (Y, Z) low

Positive

Negative

acceleration

YHYLXHXL

Interrupt Active. Default value: 0

(0: no interrupt has been generated;

1: one or more interrupt event has been generated)

Z High. Default value: 0

(0: no interrupt; 1: ZH event has occurred)

Z Low. Default value: 0

(0: no interrupt; 1: ZL event has occurred)

Y High. Default value: 0

(0: no interrupt; 1: YH event has occurred)

Y Low. Default value: 0

(0: no interrupt; 1: YL event has occurred)

X High. Default value: 0

(0: no interrupt; 1: XH event has occurred)

X Low. Default value: 0

(0: no interrupt; 1: XL event has occurred)

AN2381 Datasheet(PDF) 30 Page - STMicroelectronics

AN2381 Datasheet(HTML) 30 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47

Datasheet Download

Link URL