H3LIS331DL Datasheet, PDF (28/38 Pages) STMicroelectronics – MEMS motion sensor: low-power high-g 3-axis digital accelerometer

Register description
H3LIS331DL
7.6
BDU
BLE
FS1, FS0
SIM
Table 29. CTRL_REG4 description
Block data update. Default value: 0
(0: continuous update; 1: output registers not updated between MSB and LSB
reading)
Big/little endian data selection. Default value 0.
(0: data LSB @ lower address; 1: data MSB @ lower address)
Full scale selection. Default value: 00.
(00: ±100 g; 01: ±200 g; 11: ±400 g)
SPI serial interface mode selection. Default value: 0.
(0: 4-wire interface; 1: 3-wire interface)
The BDU bit is used to inhibit output register updates between the reading of upper and
lower register parts. In default mode (BDU = ‘0’), the lower and upper register parts are
updated continuously. When the BDU is activated (BDU = ‘1’), the content of the output
registers is not updated until both MSB and LSB are read which avoids reading values
related to different sample times.
CTRL_REG5 (24h)
Table 30. CTRL_REG5 register
0
0
0
0
0
0
TurnOn1 TurnOn0
TurnOn1,
TurnOn0
Table 31. CTRL_REG5 description
Turn-on mode selection for sleep-to-wake function. Default value: 00.
Turn-on bits are used for turning on the sleep-to-wake function.
TurnOn1
0
1
Table 32. Sleep-to-wake configuration
TurnOn0
Sleep-to-wake status
0
Sleep-to-wake function is disabled
1
Turned on: The device is in low-power mode (ODR is defined in
CTRL_REG1)
Setting TurnOn[1:0] bits to 11, the “sleep-to-wake” function is enabled. When an interrupt
event occurs, the device is turned to normal mode, increasing the ODR to the value defined
in CTRL_REG1. Although the device is in normal mode, CTRL_REG1 content is not
automatically changed to “normal mode” configuration.
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