XMOS VocalFusion XVF3510, Руководство пользователя

Страница: 40 / 86

XM-014232-PC 40
4.3.8. I 2 C MASTER PERIPHERAL INTERFACE (XVF3510-UA ONLY)
The XVF3510-UA variant provides an I 2 C 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 I
2
C Peripheral Port;
}
a mechanism to initialise devices connected to the I 2 C 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 are supported.
The following table shows the commands for the configuration of the I 2 C Master interface:
Table 4-6 I 2 C peripheral interface commands
COMMAND TYPE DIR
NUMBER
OF ARGS
NUMBER
OF
RETURN
ED
VALUES
DEFINITION
SET_I2C_READ_HEA
DER
uint8 WRITE 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_HE
ADER
uint8 READ 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 READ 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 READ 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