I2C Controller Read

The block 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, the block configures an output port. The port on the block is labeled as Status, indicating that the block outputs the status of the read operation at the output port.

The block outputs the status as a uint8 value. Each value corresponds to a data transfer status.

Data Types: uint8

Specify the I2C module on the board from which you want to read data from the I2C peripheral device.

Specify the I2C peripheral address from which you want 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 from which you want 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 I2C Register Read/Write.

Dependencies

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

Specify the data size that you want to read from the I2C peripheral device for the selected data type.

Select the data type in which you want to read from the I2C peripheral device.

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 clear 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

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, the block configures an output port. The port on the block is labeled as Status, indicating that the block outputs the status of the write operation at the output port.

The block outputs the status as a uint8 value. Each value corresponds to a data transfer status.

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