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I2C Controller Write

Write data to I2C peripheral device or I2C peripheral device register

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  • Library:

  • Embedded Coder Support Package for STMicroelectronics Discovery Boards/STM32F4xx Based Boards

    Embedded Coder Support Package for STMicroelectronics Discovery Boards/STM32F7xx Based Boards

    Embedded Coder Support Package for STMicroelectronics Discovery Boards/STM32G4xx Based Boards

    Embedded Coder Support Package for STMicroelectronics Discovery Boards/STM32H7xx Based Boards

  • I2C Controller Write block

Description

The I2C Controller Write block writes data to an I2C peripheral device that is connected to the board. Using this block, you can write data to a specific register on the I2C peripheral device.

For more information on I2C communication, see Support I2C Communication.

Ports

Input

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The port writes data to the I2C device on the board.

Data Types: int8 | uint8 | int16 | uint16 | int32 | uint32 | single | double

Output

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The port outputs 0 for a successful write operation.

Dependencies

To enable this port, select the Output error status parameter.

Data Types: uint8

Parameters

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Specify the I2C module on the board to write data to the I2C peripheral device.

The 2-byte ordering options are:

  • BigEndian - The most significant byte is sent first over the I2C bus.

  • LittleEndian - The least significant byte is sent first over the I2C bus.

Select the peripheral address source of I2C controller.

Specify the I2C peripheral address to write the data. The I2C peripheral device address is a 7-bit address.

Specify this address as an integer or in hexadecimal format by using hex2dec(), for example, ‘hex2dec(‘61’)’.

When you select this parameter, the block writes data to the I2C peripheral register that you specify in the peripheral register address parameter.

When you clear this parameter, the Send NACK at the end of data transfer and Remove stop bit at the end of data transfer parameters are displayed. Using these parameters, you can modify the write operation according to your requirements.

Specify the I2C peripheral register address to write the data.

Specify this address in 8-bit unsigned integer or in hexadecimal format. To specify the address in 8-bit unsigned integer, use uint8(), for example, ‘uint8(20)’. To specify the address in hexadecimal format, use hex2dec(), for example, ‘hex2dec(‘20’)’.

For more information on register read/write, see I2C Register Read/Write.

Dependencies

This parameter appears only when you select Enable register access parameter.

When the parameter is not selected, the block sends a STOP condition. This condition indicates that the block has terminated the data transmission and that the I2C bus is free for any other I2C Controller block to initiate the new read/write operation.

When you select this parameter, the block sends another START condition followed by an address and read/write bit. The block sends any number of start conditions recursively. Such a repeated START condition allows write operations to the peripheral devices without releasing the bus. No other Controller block interrupts the operation.

Dependencies

To enable this parameter, deselect the Enable register access parameter.

When you select this parameter, the I2C Controller Read block sends a NACK (Not Acknowledge) bit to the peripheral device with the final byte.

When the peripheral device receives the NACK, it waits for a STOP condition from the I2C Controller block. The controller block generates either a STOP condition to abort the transfer or a repeated START condition to start a new transfer.

When you deselect this parameter, the I2C Controller Read block sends an ACK (Acknowledge) bit to the peripheral device at the end of every byte. The ACK indicates that the I2C Controller Read block is ready to read the next byte from the peripheral device.

Dependencies

To enable this parameter, deselect the Enable register access parameter.

When you select this parameter, an output port, labeled as Status, becomes available.

See Also