ZMOD4450 Datasheet

© 2021 Renesas Electronics Corporation

13

June 30, 2021

10. I2C Interface and Data Transmission Protocol

The I2C slave device interface supports various bus speeds: Standard Mode (≤100kHz) and Fast Mode (≤400kHz).

one used for conventional EEPROM devices. The register to read/write is selected by a register address pointer. This address pointer must be

set during an I2C write operation. For read access a repeated START condition but no STOP condition should be sent. After transmission of a

For an example of the I2C data transmission protocol, see Figure 5. For information on I2C bus timing, see Figure 6. For I2C bus characteristics,

see Table 9, which explains how to set up the interface. All other values are according to the I2C standard. Although the ZMOD4410 has an

I2C interface, the user is not intended to modify any registers because a configuration change will affect the sensor module’s performance,

reliability, and accuracy. The API provided with the downloadable firmware package on the website manages all necessary sensor module

communication.

To validate the general MCU-specific I2C read/write driver without the use of Renesas libraries, it is possible to write random values to registers

0x88 to 0x8B and read them afterwards. After this register testing, erase the testing code and reset the device by disconnecting the power

support; otherwise the device may not operate properly.

Figure 5. I2C Data Transmission Protocol

Write

Read

Write

From master to slave

From slave to master

S

START condition

P

STOP condition

A

N

Acknowledge

Not acknowledge

WRITE Access RAM

READ Access NVM and RAM

0

S

Slave Addr

7 Bit

1

A

Address

8 Bit

N P

Data

8 Bit

A S

Slave Addr

7 Bit

A

A

Data

8 Bit

A

Data

8 Bit

...

0

S

Slave Addr

7 Bit

A

Address

P

Data

8 Bit

A

A

Data

8 Bit

A

Data

8 Bit

...

A