lejos.nxt
Interface I2CPort

All Superinterfaces:

BasicSensorPort, SensorConstants

All Known Implementing Classes:

RemoteSensorPort, SensorPort

public interface I2CPort
extends BasicSensorPort

Abstraction for a port that supports I2C sensors.

Author:

Lawrie Griffiths

Field Summary

static int	ALWAYS_ACTIVE Keep the i2c driver active between requests
static int	ERR_ABORT Operation aborted
static int	ERR_BUS_BUSY Bus is busy
static int	ERR_BUSY Port is busy
static int	ERR_FAULT Data error during transaction
static int	ERR_INVALID_LENGTH Read/Write request too large
static int	ERR_INVALID_PORT Invalid port number, or port is not enabled
static int	HIGH_SPEED Use high speed I/O (125KHz)
static int	LEGO_MODE Use Lego compatible i2c protocol (default)
static int	MAX_IO Maximum read/write request length
static int	NO_RELEASE Do not release the i2c bus between requests
static int	STANDARD_MODE Use standard i2c protocol

Fields inherited from interface lejos.nxt.SensorConstants

BLACK, BLANK_INDEX, BLUE, BLUE_INDEX, GREEN, GREEN_INDEX, MAX_AD_RAW, MAX_TYPE, MIN_TYPE, MODE_ANGLESTEP, MODE_BOOLEAN, MODE_CELSIUS, MODE_FARENHEIT, MODE_PCTFULLSCALE, MODE_PERIODCOUNTER, MODE_RAW, MODE_TRANSITIONCNT, RED, RED_INDEX, TYPE_ANGLE, TYPE_COLORBLUE, TYPE_COLORFULL, TYPE_COLORGREEN, TYPE_COLORNONE, TYPE_COLORRED, TYPE_CUSTOM, TYPE_HISPEED, TYPE_LIGHT_ACTIVE, TYPE_LIGHT_INACTIVE, TYPE_LOWSPEED, TYPE_LOWSPEED_9V, TYPE_NO_SENSOR, TYPE_REFLECTION, TYPE_SOUND_DB, TYPE_SOUND_DBA, TYPE_SWITCH, TYPE_TEMPERATURE, WHITE, YELLOW

Method Summary

void	i2cDisable() Disable the device.
void	i2cEnable(int mode) Enable the low level device
int	i2cStatus() Check to see the status of the port/device
int	i2cTransaction(int deviceAddress, byte[] writeBuf, int writeOffset, int writeLen, byte[] readBuf, int readOffset, int readLen) High level i2c interface.

Methods inherited from interface lejos.nxt.BasicSensorPort

getMode, getType, setMode, setType, setTypeAndMode

Field Detail

STANDARD_MODE

static final int STANDARD_MODE

Use standard i2c protocol

See Also:

Constant Field Values

LEGO_MODE

static final int LEGO_MODE

Use Lego compatible i2c protocol (default)

See Also:

Constant Field Values

ALWAYS_ACTIVE

static final int ALWAYS_ACTIVE

Keep the i2c driver active between requests

See Also:

Constant Field Values

NO_RELEASE

static final int NO_RELEASE

Do not release the i2c bus between requests

See Also:

Constant Field Values

HIGH_SPEED

static final int HIGH_SPEED

Use high speed I/O (125KHz)

See Also:

Constant Field Values

MAX_IO

static final int MAX_IO

Maximum read/write request length

See Also:

Constant Field Values

ERR_INVALID_PORT

static final int ERR_INVALID_PORT

Invalid port number, or port is not enabled

See Also:

Constant Field Values

ERR_BUSY

static final int ERR_BUSY

Port is busy

See Also:

Constant Field Values

ERR_FAULT

static final int ERR_FAULT

Data error during transaction

See Also:

Constant Field Values

ERR_INVALID_LENGTH

static final int ERR_INVALID_LENGTH

Read/Write request too large

See Also:

Constant Field Values

ERR_BUS_BUSY

static final int ERR_BUS_BUSY

Bus is busy

See Also:

Constant Field Values

ERR_ABORT

static final int ERR_ABORT

Operation aborted

See Also:

Constant Field Values

Method Detail

i2cEnable

void i2cEnable(int mode)

Enable the low level device

Parameters:

mode - One or more of the mode bits above.

i2cDisable

void i2cDisable()

Disable the device.

i2cStatus

int i2cStatus()

Check to see the status of the port/device

Returns:

0 if ready -1: Invalid device -2: Device busy -3: Device fault -4: Buffer size error. -5: Bus is busy

i2cTransaction

int i2cTransaction(int deviceAddress,
                   byte[] writeBuf,
                   int writeOffset,
                   int writeLen,
                   byte[] readBuf,
                   int readOffset,
                   int readLen)

High level i2c interface. Perform a complete i2c transaction and return the results. Writes the specified data to the device and then reads the requested bytes from it. The address is given as an 8 bit value. Bit 0 must be always be zero. Bit 1 to 7 specify the 7 bit i2c address.

Parameters:

deviceAddress - The I2C device address.

writeBuf - The buffer containing data to be written to the device.

writeOffset - The offset of the data within the write buffer

writeLen - The number of bytes to write.

readBuf - The buffer to use for the transaction results

readOffset - Location to write the results to

readLen - The length of the read

Returns:

< 0 error otherwise the number of bytes read