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LSM330 Datasheet, PDF (27/75 Pages) STMicroelectronics – Power-down and sleep modes
LSM330
Functionality
4.3.6
Stream-to-FIFO mode
In Stream-to-FIFO mode, data from yaw, pitch and roll measurements are stored in the
FIFO. A watermark interrupt can be enabled on the pin DRDY_G/INT2_G, setting the
I2_WTM bit in CTRL_REG3_G (22h) in order to be raised when the FIFO is filled to the level
specified by the WTM [4:0] bits of FIFO_CTRL_REG_G (2Eh). The FIFO continues filling
until it's full (32 slots of 16-bit data for yaw, pitch and roll). When full, the FIFO discards the
older data as the new data arrive. Once a trigger event occurs (related to INT1_CFG_G
(30h) register events), the FIFO starts operating in FIFO mode. Refer to the following figure.
Figure 11. Stream-to-FIFO mode
xi,y i,z i
x0
y0
z0
x1
y1
z1
x2
y2
z2
x 30
y 30
z 30
x 31
y 31
z 31
xi,yi,z i
x0
y0
z0
x1
y1
z1
x2
y2
z2
x 31
y 31
z 31
4.3.7
Stream Mode
FIFO Mode
Trigger event
AM07236v1
Retrieving data from FIFO
FIFO data is read from OUT_X_L_G (28h), OUT_X_H_G (29h) and OUT_Y_L_G (2Ah),
OUT_Y_H_G (2Bh) and OUT_Z_L_G (2Ch), OUT_Z_H_G (2Dh). When the FIFO is in
Stream, Stream-to-FIFO or FIFO mode, a read from the OUT_X_L_G (28h), OUT_X_H_G
(29h), OUT_Y_L_G (2Ah), OUT_Y_H_G (2Bh) and OUT_Z_L_G (2Ch), OUT_Z_H_G (2Dh)
registers provides the data stored in the FIFO.
Each time data is read from the FIFO, the oldest pitch, roll and yaw data are placed in the
OUT_X_L_G (28h), OUT_X_H_G (29h), OUT_Y_L_G (2Ah), OUT_Y_H_G (2Bh) and
OUT_Z_L_G (2Ch), OUT_Z_H_G (2Dh) registers and both single read and read_burst (X, Y
and Z with autoincremental address) operations can be used. When data included in
OUT_Z_H_G (2Dh) is read, the system restarts to read information from OUT_X_L_G
(28h).
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