LSM9DS0 Datasheet, PDF (23/74 Pages) STMicroelectronics – iNEMO inertial module 3D accelerometer, 3D gyroscope, 3D magnetometer

LSM9DS0
Functionality
4.2.2
4.2.3
4.2.4
4.2.5
4.2.6
and burst the significant data out from the FIFO. This buffer can work accordingly in four
different modes: Bypass mode, FIFO mode, Stream mode and Stream-to-FIFO mode. Each
mode is selected by the FIFO_MODE bits in FIFO_SRC_REG (2Fh). Programmable
watermark level, FIFO_Empty or FIFO_Full events can be enabled to generate dedicated
interrupts on the INT1_XM/INT2_XM pin (configured through FIFO_SRC_REG (2Fh)).
Bypass mode
In Bypass mode, the FIFO is not operational and for this reason it remains empty. For each
channel only the first address is used. The remaining FIFO slots are empty.
FIFO mode
In FIFO mode, data from the X, Y and Z channels are stored in the FIFO. A watermark
interrupt can be enabled (FIFO_WTMK_EN bit in FIFO_CTRL_REG (2Eh)) in order to be
raised when the FIFO is filled to the level specified in the FIFO_WTMK_LEVEL bits of
FIFO_CTRL_REG (2Eh). The FIFO continues filling until it is full (32 slots of data for X, Y
and Z). When full, the FIFO stops collecting data from the input channels.
Stream mode
In Stream mode, data from the X, Y and Z measurements are stored in the FIFO. A
watermark interrupt can be enabled and set as in FIFO mode. The FIFO continues filling
until it is full (32 slots of data for X, Y and Z). When full, the FIFO discards the older data as
the new data arrives.
Stream-to-FIFO mode
In Stream-to-FIFO mode, data from the X, Y and Z measurements is stored in the FIFO. A
watermark interrupt can be enabled (FIFO_WTMK_EN bit in FIFO_CTRL_REG (2Eh)) in
order to be raised when the FIFO is filled to the level specified in the FIFO_WTMK_LEVEL
bits of FIFO_CTRL_REG (2Eh). The FIFO continues filling until it is full (32 slots of 8-bit data
for X, Y and Z). When full, the FIFO discards the older data as the data new arrives. Once a
trigger event occurs, the FIFO starts operating in FIFO mode.
Retrieving data from FIFO
A read operation to the OUT_X_L_A (28h), OUT_X_H_A (29h), OUT_Y_L_A (2Ah),
OUT_Y_H_A (2Bh) or OUT_Z_L_A (2Ch), OUT_Z_H_A (2Dh) registers provides the data
stored in the FIFO. Each time data is read from the FIFO, the oldest X, Y and Z data are
placed in the OUT_X_L_A (28h), OUT_X_H_A (29h), OUT_Y_L_A (2Ah), OUT_Y_H_A
(2Bh) and OUT_Z_L_A (2Ch), OUT_Z_H_A (2Dh) registers and both single read and
read_burst operations can be used.
DocID024763 Rev 2
23/74
74