com.pi4j.io.i2c

Interface I2CDevice

All Known Implementing Classes:

I2CDeviceImpl

public interface I2CDevice

This is abstraction of an i2c device. It allows data to be read or written to the device.

Author:

Daniel Sendula, refactored by RasPelikan

Method Summary

Modifier and Type	Method and Description
int	getAddress()
void	ioctl(long command, ByteBuffer data, IntBuffer offsets) Runs an ioctl on this device.
void	ioctl(long command, int value) Runs an ioctl on this device.
int	read() This method reads one byte from the i2c device.
int	read(byte[] buffer, int offset, int size) This method reads bytes directly from the i2c device to given buffer at asked offset.
int	read(byte[] writeBuffer, int writeOffset, int writeSize, byte[] readBuffer, int readOffset, int readSize) This method writes and reads bytes to/from the i2c device in a single method call
int	read(int address) This method reads one byte from the i2c device.
int	read(int address, byte[] buffer, int offset, int size) This method reads bytes from the i2c device to given buffer at asked offset.
void	write(byte b) This method writes one byte directly to i2c device.
void	write(byte[] buffer) This method writes all bytes included in the given buffer directly to the i2c device.
void	write(byte[] buffer, int offset, int size) This method writes several bytes directly to the i2c device from given buffer at given offset.
void	write(int address, byte b) This method writes one byte to i2c device.
void	write(int address, byte[] buffer) This method writes all bytes included in the given buffer directoy to the register address on the i2c device
void	write(int address, byte[] buffer, int offset, int size) This method writes several bytes to the i2c device from given buffer at given offset.

Method Detail

getAddress

int getAddress()

Returns:

The address for which this instance is constructed for.

write

void write(byte b)
    throws IOException

This method writes one byte directly to i2c device.

Parameters:

b - byte to be written

Throws:

IOException - thrown in case byte cannot be written to the i2c device or i2c bus

write

void write(byte[] buffer,
           int offset,
           int size)
    throws IOException

This method writes several bytes directly to the i2c device from given buffer at given offset.

Parameters:

buffer - buffer of data to be written to the i2c device in one go

offset - offset in buffer

size - number of bytes to be written

Throws:

IOException - thrown in case byte cannot be written to the i2c device or i2c bus

write

void write(byte[] buffer)
    throws IOException

This method writes all bytes included in the given buffer directly to the i2c device.

Parameters:

buffer - buffer of data to be written to the i2c device in one go

Throws:

IOException - thrown in case byte cannot be written to the i2c device or i2c bus

write

void write(int address,
           byte b)
    throws IOException

This method writes one byte to i2c device.

Parameters:

address - local address in the i2c device

b - byte to be written

Throws:

IOException - thrown in case byte cannot be written to the i2c device or i2c bus

write

void write(int address,
           byte[] buffer,
           int offset,
           int size)
    throws IOException

This method writes several bytes to the i2c device from given buffer at given offset.

Parameters:

address - local address in the i2c device

buffer - buffer of data to be written to the i2c device in one go

offset - offset in buffer

size - number of bytes to be written

Throws:

IOException - thrown in case byte cannot be written to the i2c device or i2c bus

write

void write(int address,
           byte[] buffer)
    throws IOException

This method writes all bytes included in the given buffer directoy to the register address on the i2c device

Parameters:

address - local address in the i2c device

buffer - buffer of data to be written to the i2c device in one go

Throws:

IOException - thrown in case byte cannot be written to the i2c device or i2c bus

read

int read()
  throws IOException

This method reads one byte from the i2c device. Result is between 0 and 255 if read operation was successful, else a negative number for an error.

Returns:

byte value read: positive number (or zero) to 255 if read was successful. Negative number if reading failed.

Throws:

IOException - thrown in case byte cannot be read from the i2c device or i2c bus

read

int read(byte[] buffer,
         int offset,
         int size)
  throws IOException

This method reads bytes directly from the i2c device to given buffer at asked offset.

Parameters:

buffer - buffer of data to be read from the i2c device in one go

offset - offset in buffer

size - number of bytes to be read

Returns:

number of bytes read

Throws:

IOException - thrown in case byte cannot be read from the i2c device or i2c bus

read

int read(int address)
  throws IOException

This method reads one byte from the i2c device. Result is between 0 and 255 if read operation was successful, else a negative number for an error.

Parameters:

address - local address in the i2c device

Returns:

byte value read: positive number (or zero) to 255 if read was successful. Negative number if reading failed.

Throws:

IOException - thrown in case byte cannot be read from the i2c device or i2c bus

read

int read(int address,
         byte[] buffer,
         int offset,
         int size)
  throws IOException

This method reads bytes from the i2c device to given buffer at asked offset.

Parameters:

address - local address in the i2c device

buffer - buffer of data to be read from the i2c device in one go

offset - offset in buffer

size - number of bytes to be read

Returns:

number of bytes read

Throws:

IOException - thrown in case byte cannot be read from the i2c device or i2c bus

ioctl

void ioctl(long command,
           int value)
    throws IOException

Runs an ioctl on this device.

Throws:

IOException

See Also:

LinuxFile.ioctl(long, int)

ioctl

void ioctl(long command,
           ByteBuffer data,
           IntBuffer offsets)
    throws IOException

Runs an ioctl on this device.

Throws:

IOException

See Also:

LinuxFile.ioctl(long, ByteBuffer, IntBuffer)

read

int read(byte[] writeBuffer,
         int writeOffset,
         int writeSize,
         byte[] readBuffer,
         int readOffset,
         int readSize)
  throws IOException

This method writes and reads bytes to/from the i2c device in a single method call

Parameters:

writeBuffer - buffer of data to be written to the i2c device in one go

writeOffset - offset in write buffer

writeSize - number of bytes to be written from buffer

readBuffer - buffer of data to be read from the i2c device in one go

readOffset - offset in read buffer

readSize - number of bytes to be read

Returns:

number of bytes read

Throws:

IOException - thrown in case byte cannot be read from the i2c device or i2c bus