I2C Master peripheral interface (XVF3610-UA Only)

The XVF3610-UA variant provides an I²C master interface which can be used as:

• a bridge from the USB interface, i.e. VFCTRL_USB commands can be used from the host to read and write devices connected to the I²C Peripheral Port;

• a mechanism to initialise devices connected to the I²C Peripheral Port by incorporating commands into the Data Partition (in the external flash), which are executed at boot time.

The interface supports:

• 100kbps fixed speed

• 7bit addressing only

• Byte I²C register read/writes

The following table shows the commands for the configuration of the I²C Master interface:

Table 43 I²C peripheral interface commands

COMMAND	TYPE	NUM ARGS	NUM VALUES	DEFINITION
SET_I2C_READ _HEADER	uint8	3	0	Set the parameters to be used by the next GET_I2C, or GET_I2C_WITH_REG command. Arguments: 1: The 7-bit I2C slave device address. 2: The register address within the device. 3: The number of bytes to read.
GET_I2C_READ _HEADER	uint8	0	3	Get the parameters to be used by the next GET_I2C, or GET_I2C_WITH_REG command. Returned values: 1: The 7-bit I2C slave device address. 2: The register address within the device. 3: The number of bytes to read.
GET_I2C	uint8	0	56	Read from an I2C device defined by the SET_I2C_READ_HEADER command. Returned values: 1 to 56: The number of bytes read as defined by the SET_I2C_READ_HEADER command followed by additional undefined values. The number of bytes read from the I2C device when executing GET_I2C is set using SET_I2C_READ_HEADER
GET_I2C_WITH_REG	uint8	0	56	Read from the register of an I2C device as defined by the SET_I2C_READ_HEADER command. Returned values: 1 to 56: The number of bytes read as defined by the SET_I2C_READ_HEADER command followed by additional undefined values. The number of bytes read from the I2C device when executing GET_I2C is set using SET_I2C_READ_HEADER
SET_I2C	uint8	56	0	Write to an I2C slave device. Arguments: 1: The 7-bit I2C slave device address. 2: The number of data bytes to write (n). 3 to 56: Data bytes. All 54 values must be given but only n will be sent.
SET_I2C_WITH_REG	uint8	56	0	Write to a specific register of an I2C slave device. Arguments: 1: The 7-bit I2C slave device address. 2: The register address within the device. 3: The number of data bytes to write (n). 4 to 56: Data bytes. All 53 values must be given but only n will be sent.

Fig. 32 I2C protocol for register reads

Fig. 33 I2C protocol for register writes

• raw I²C read/writes may be performed.

Fig. 34 I2C protocol for raw reads and writes