I2C Controller Read

The port reads vector data from an I2C device on the board. The size of the data is the value that you specify in the Data size parameter.

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

When you select the Output error status parameter, an output port, labeled as Status, becomes available.

The port outputs the status of each read request as mentioned in the following table:

Data Types: uint8

Specify the I2C module on the board to read data from the I2C Peripheral devices.

Specify the I2C Peripheral address to read the data. You can specify this address in hexadecimal format hex2dec(), for example, ‘hex2dec(‘20’)’.

The 2-byte ordering options are:

When you select this parameter, the block reads data from 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 read operation according to your requirements.

Specify the I2C register address to read the data.

Specify this address as an integer or in hexadecimal format by using hex2dec(), for example, ‘hex2dec(‘20’)’.

For more information on register read/write, see .

Dependencies

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

Select the data type in which you want to read from the I2C Peripheral devices.

Specify the data size that you want to read from the I2C Peripheral devices for the selected data type.

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

When the Peripheral devices 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 clear this parameter, the I2C Controller Read block sends an ACK (Acknowledge) bit to the Peripheral devices 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 devices.

Dependencies

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

When you clear this parameter, 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

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

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

The port outputs 0 for a successful read operation.

Specify how often the I2C Controller Read block reads data from the I2C Peripheral devices. When you specify this parameter as-1, the block inherits its sample time based on the context of the block within the model.