CMA3000-D0X VTI Hamlin, CMA3000-D0X Datasheet - Page 19

• Manufacturer Part Number: CMA3000-D0X
• Description: Cma3000-d0x Series 3-axis Accelerometer
• Manufacturer: VTI Hamlin

4.2 I
4.2.1
4.2.1.1
4.2.1.2
4.2.2
VTI Technologies Oy
www.vti.fi
2
I
Examples of I
C Interface
2
C frame format
I
I
2
2
C write mode
C read mode
In cases with multiple slaves in SPI bus it is recommended that I2C transmission is disabled by
setting I2C_DIS bit to '1' in CRTL register. After CMA3000 start up the I2C_DIS bit is always 0 (I
transmission enabled).
I
master is defined as a micro controller providing the serial clock (SCL), and the slave as any
integrated circuit receiving the SCL clock from the master. The CMA3000 sensor always operates
as a slave device in master-slave operation mode. When using an SPI interface, a hardware
addressing is used (slaves have dedicated CSB signals), the I
addressing (slave devices have dedicated bit patterns as addresses). The default I
address for CMA3000 is 00011100b (1Ch) (pre-programmed during CMA3000 production).
The CMA3000 is compatible to the Philips I
interface are:
In I
to be written.
The read mode operates as described in Philips I
content of the register which address is defined in I2C read frame. Read data is acknowledged by
I
Examples of I
address bits (1Ch=0011100b) followed by the R/W bit.
Figure 10 I
2
2
C is a 2-wire serial interface. It consists of one master device and one or more slave devices. The
C master.
2
C write mode, the first 8 bits after device address define the CMA3000 internal register address
2
C communication
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-
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-
2
C format
2
7-bit addressing, CMA3000 I
Supports standard mode and fast mode
Start / Restart / Stop
Slave transceiver mode
Designed for low power consumption
C communication are presented below in Figure 10. Address byte includes 7 device
Doc.Nr. 8281000.12
2
C device address is 1Ch
2
C specification V2.1. Main used features of the I
2
C specification. I
2
C interface uses a software based
2
C read operation returns the
CMA3000-D0X Series
2
C device
Rev. 0.12
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2
2
C
C