LSM330 Datasheet, PDF (34/75 Pages) STMicroelectronics – Power-down and sleep modes

Digital interfaces
LSM330
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 communication format presented, MAK is Master Acknowledge and NMAK is No
Master Acknowledge.
Default address:
The SDO/SA0 pins (SDO_A / SDO_G) can be used to modify the least significant bits of the
device address.The linear acceleration sensor slave address is 00111xxb whereas the xx
bits are modified by the SDO_A pin. If the SDO/A pin is connected to the supply voltage, the
address is 0011101b, otherwise if the SDO/A pin is connected to ground, the address is
0011110b.This solution allows to connect and address two different accelerometers to the
same I²C line.
The angular rate sensor slave address is 110101xb, whereas the x bit is modified by the
SDO/G bit. If the SDO_G pin is connected to the supply voltage, LSb is ‘1’ (address
1101011b), otherwise, if the SDO_G pin is connected to ground, the LSb value is ‘0’
(address 1101010b).
The slave addresses are 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 direction unchanged. Table 15 and
Table 16 explain how the SAD+Read/Write bit pattern is composed, listing all the possible
configurations.
Linear acceleration sensor: the default (factory) 7-bit slave address is
00111xxb.
Command
Read
Write
Read
Write
Table 15. Linear acceleration SAD+Read/Write patterns
SAD[6:2] SAD[1] = SDO_A SAD[0] = SDO_A R/W
SAD+R/W
00111
1
0
1
00111101 (3Dh)
00111
1
0
0
00111100 (3Ch)
00111
0
00111
0
1
1
00111011 (3Bh)
1
0
00111010 (3Ah)
Angular rate sensor: the default (factory) 7-bit slave address is 110101xb.
Command
Read
Write
Read
Write
Table 16. Angular rate SAD+Read/Write patterns
SAD[6:1]
SAD[0] = SDO_G
R/W
SAD+R/W
110101
0
1
11010101 (D5h)
110101
0
110101
1
0
11010100 (D4h)
1
11010111 (D7h)
110101
1
0
11010110 (D6h)
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