LPS25HB Datasheet, PDF (29/40 Pages) STMicroelectronics – MEMS pressure sensor: 260-1260 hPa absolute digital output barometer

LPS25HB
Register description
output registers is not updated until both MSB and LSB are read, avoiding the reading of
values related to different samples.
The RESET_AZ bit is used to reset the AutoZero function. Resetting REF_P_H (0Ah),
REF_P_L (09h) and REF_P_XL (08h) sets the pressure reference registers RPDS_H (3Ah)
and RPDS_L (39h) to the default value. RESET_AZ is self-cleared. For the AutoZero
function please refer to CTRL_REG2 (21h).
The SIM bit selects the SPI serial interface mode:
• 0: (default value) 4-wire SPI interface mode selected;
• 1: 3-wire SPI interface mode selected.
8.7
CTRL_REG2 (21h)
Control register 2
7
BOOT
6
FIFO_EN
5
4
STOP_ON_FT FIFO_MEAN_
3
I2C_EN
2
SWRESET
1
0
AUTO_ZERO ONE_SHOT
BOOT
FIFO_EN
STOP_ON_FTH
FIFO_MEAN_-
DEC
I2C_EN
SWRESET
AUTOZERO
ONE_SHOT
Reboot memory content. Default value: 0.
(0: normal mode; 1: reboot memory content). The bit is self-cleared when the BOOT
is completed.
FIFO enable. Default value: 0.
(0: disable; 1: enable)
Stop on FIFO threshold. Enable FIFO watermark level use. Default value 0
(0: disable; 1: enable).
Register address automatically incremented during a multiple byte access with a
serial interface (I²C or SPI). Default value 1.
(0: disable; 1 enable)
I²C interface enabled. Default value 0.
(0: I²C enabled;1: I²C disabled)
Software reset. Default value: 0.
(0: normal mode; 1: software reset).
The bit is self-cleared when the reset is completed.
Autozero enable. Default value: 0.
(0: normal mode; 1: Autozero enabled)
One shot mode enable. Default value: 0.
(0: idle mode; 1: a new dataset is acquired)
The BOOT bit is used to refresh the content of the internal registers stored in the Flash
memory block. At device power-up the content of the Flash memory block is transferred to
the internal registers related to the trimming functions to allow correct behavior of the device
itself. If for any reason the content of the trimming registers is modified, it is sufficient to use
this bit to restore the correct values. When the BOOT bit is set to ‘1’, the content of the
internal Flash is copied inside the corresponding internal registers and is used to calibrate
the device. These values are factory trimmed and they are different for every device. They
allow correct behavior of the device and normally they should not be changed. At the end of
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