LSM9DS0 Datasheet, PDF (33/74 Pages) STMicroelectronics – iNEMO inertial module 3D accelerometer, 3D gyroscope, 3D magnetometer

LSM9DS0
Digital interfaces
some other function, it can hold the clock line, SCL LOW to force the transmitter into a wait
state. Data transfer only continues when the receiver is ready for another byte and releases
the data line. If a slave receiver doesn’t acknowledge the slave address (i.e. it is not able to
receive because it is performing some real-time function) the data line must be left HIGH by
the slave. The master can then abort the transfer. A LOW to HIGH transition on the SDA line
while the SCL line is HIGH is defined as a STOP condition. Each data transfer must be
terminated by the generation of a STOP (SP) condition.
In order to read multiple bytes, it is necessary to assert the most significant bit of the sub-
address field. In other words, SUB(7) must be equal to 1 while SUB(6-0) represents the
address of first register to be read.
In the presented communication format MAK is Master Acknowledge and NMAK is No
Master Acknowledge.
Default address:
The SDO/SA0 pins (SDO_XM/SA0_XM or SDO_G/SA0_G) can be used to modify the least
significant bit of the device address. If the SA0 pin is connected to the voltage supply, LSb is
‘1’ (ex. address 0011101b) else if SA0 pad is connected to ground, the LSb value is ‘0’ (ex.
address 0011110b).
The slave address is completed with a Read/Write bit. If the bit was ‘1’ (Read), a repeated
START (SR) condition will have to be issued after the two sub-address bytes; if the bit is ‘0’
(Write) the master will transmit to the slave with the direction unchanged. Table 15 and
Table 16 explain how the SAD+Read/Write bit pattern is composed, listing all the possible
configurations.
Linear acceleration and magnetic sensor address:
Table 15. Linear acceleration and magnetic sensor SAD+read/write patterns
Command SDO_XM/SA0_XM pin SAD[6:2] SAD[1:0]
R/W
SAD+R/W
Read
0
00111
10
1
00111101 (3D)
Write
Read
Write
0
00111
10
0
00111100 (3C)
1
00111
01
1
00111011 (3B)
1
00111
01
0
00111010 (3A)
Angular rate sensor address:
Command
Read
Write
Read
Write
Table 16. Angular rate SAD+read/write patterns
SAD[6:1] SAD[0] = SDO_G/SA0_G pin
R/W
SAD+R/W
110101
0
1
11010101 (D5h)
110101
0
0
11010100 (D4h)
110101
1
1
11010111 (D7h)
110101
1
0
11010110 (D6h)
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