LSM320HAY30 STMicroelectronics, LSM320HAY30 Datasheet - Page 22

• Manufacturer Part Number: LSM320HAY30
• Description: Mems Motion Sensor Module 3d Digital Accelerometer And 2d Pitch And Yaw Analog Gyroscope
• Manufacturer: STMicroelectronics

Digital interfaces
Table 13.
6.2
22/42
Master
Slave
ST SAD+W
Table 11.
Table 12.
Transfer when master is receiving (reading) multiple bytes of data from slave
Data are transmitted in byte format (DATA). Each data transfer contains 8 bits. The number
of bytes transferred per transfer is unlimited. Data is transferred with the most significant bit
(MSb) first. If a receiver cannot receive another complete byte of data until it has performed
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 does not acknowledge the slave address (i.e. it is not able to
receive because it is performing a 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 the first register to be read.
In the presented communication format MAK is Master Acknowledge and NMAK is No
Master Acknowledge.
SPI bus interface
The LSM320HAY30 SPI is a bus slave. The SPI allows writing and reading of the registers
of the device.
The serial interface interacts with the outside world with 4 wires: CS, SPC, SDI and SDO.
Master
Master
Slave
Slave
ST
SAK
ST
Transfer when master is writing multiple bytes to slave
Transfer when master is receiving (reading) one byte of data from slave
SAD + W
SUB
SAD + W
SAK
SAK
SR SAD+R
SAK
Doc ID 16917 Rev 1
SUB
SUB
SAK
SAK
SAK
SR
DATA
SAD + R
DATA
MAK
DATA
SAK
SAK
MAK
DATA
DATA
DATA
LSM320HAY30
NMAK
SAK
NMAK
SP
SP
SP