com.sun.spot.peripheral.radio
Interface ILowPanPacketDispatcher

All Known Implementing Classes:

LowPanPacketDispatcher

public interface ILowPanPacketDispatcher

Multiplexes traffic for up to 255 protocols over the radio connection between two Spots or between a host application and a spot. Implementations (named LowPanPacketDispatcher) provide the platform-specific implementations.

Protocols (not to be confused with the use of the word "Protocol" in the GCF framework) are identified by unique byte values. To implement a protocol, first pick a protocol number not in conflict with other protocols. To send radio packets for that protocol, route them via the LowPanPacketDispatcher on your platform:

...
LowPanPacketDispatcher.getInstance().sendPacket(MY_PROTOCOL_NUMBER, myRadioPacket);
...

To receive and manage the traffic associated with your protocol, you need to register an IProtocolManager:

...
LowPanPacketDispatcher.getInstance().addProtocol(MY_PROTOCOL_NUMBER, myProtocolManager);
...

See IProtocolManager for more details.

ILowPanPacketDispatcher also provides a set of radio control facilities for application developers such as controlling power output, channel and PAN ID.

Author:

Syntropy

Field Summary

static short	DEFAULT_PAN_ID Default PAN id to use.
static byte	LOWPAN_DATA_OFFSET The offset into RadioPackets at which data starts.

Method Summary

void	addProtocol(byte protocolNum, IProtocolManager protocolMan) Register a protocol to send and receive radio packets.
void	closeBaseStation() Used in the host to close down the base station - a no-op if called on a Spot
int	getChannelNumber() Answer the current channel number (between 11 and 26).
long	getIEEEAddress()
int	getOutputPower() Answer the radio output power in decibels.
short	getPanId() Answer the current pan ID.
void	initBaseStation() Used in the host to initialize the base station - a no-op if called on a Spot
boolean	isLoggingConnections()
void	removeProtocol(byte protocolNum) Deregister an existing protocol so that it no longer receives radio packets
void	sendPacket(byte protocolNum, RadioPacket rp) Send a radio packet on a given protocol.
void	setChannelNumber(int channel) Set the current channel number (between 11 and 26).
void	setLogConnections(boolean logConnections) Select whether connection addition and removal is being logged to System.out
void	setOutputPower(int power) Set the radio output power in decibels (between -32 and +31).
void	setPanId(short pid) Set the pan ID (should not be -1 or -2, which are reserved in the I802.15.4 standard).
void	startMAC() Start the MAC layer device, if it's not already started.
void	turnOffReceiver() Turn off the radio receiver
void	turnOnReceiver() Turn on the radio receiver
void	turnOnReceiver(int period) Turn on the radio receiver for a fixed period

Field Detail

DEFAULT_PAN_ID

static final short DEFAULT_PAN_ID

Default PAN id to use.

See Also:

Constant Field Values

LOWPAN_DATA_OFFSET

static final byte LOWPAN_DATA_OFFSET

The offset into RadioPackets at which data starts. Clients should start writing and reading RadioPackets with code like this: myRadioPacket.setMACPayloadAt(LOWPAN_DATA_OFFSET, someValue);

See Also:

Constant Field Values

Method Detail

addProtocol

void addProtocol(byte protocolNum,
                 IProtocolManager protocolMan)

Register a protocol to send and receive radio packets.

Parameters:

protocolNum - - the unique number to identify the protocol (0..255)

protocolMan - - the object that will receive incoming radio packets associated with the protocol

Throws:

IllegalArgumentException - if the protocolNumber is already being handled by another IProtocolManager

removeProtocol

void removeProtocol(byte protocolNum)

Deregister an existing protocol so that it no longer receives radio packets

Parameters:

protocolNum - - the unique number to identify the protocol to deregister.

Throws:

IllegalArgumentException - if protocolNum isn't currently being handled

sendPacket

void sendPacket(byte protocolNum,
                RadioPacket rp)
                throws NoAckException,
                       ChannelBusyException

Send a radio packet on a given protocol. The caller is responsible for ensuring that the radio packet is addressed correctly and has the correct content. The caller should write content to the packet within the MAC payload area at or after the LOWPAN_DATA_OFFSET:

...
rp.setMACPayloadAt(ILowPanPacketDispatcher.LOWPAN_DATA_OFFSET, aVal);
...


Parameters:

protocolNum - - the protocl number associated with the outgoing packet

rp - - the radio packet to send

Throws:

NoAckException

ChannelBusyException

getChannelNumber

int getChannelNumber()

Answer the current channel number (between 11 and 26).

Returns:

current channel number

setChannelNumber

void setChannelNumber(int channel)

Set the current channel number (between 11 and 26).

Parameters:

channel - - the new channel number

getPanId

short getPanId()

Answer the current pan ID.

Returns:

current pan ID

setPanId

void setPanId(short pid)

Set the pan ID (should not be -1 or -2, which are reserved in the I802.15.4 standard).

Parameters:

pid - - the new pan ID

startMAC

void startMAC()

Start the MAC layer device, if it's not already started.

setOutputPower

void setOutputPower(int power)

Set the radio output power in decibels (between -32 and +31). NB. The range given is the I802.15.4 standard range. In practice, for the CC2420 radio, this will mean maximum power for all values from 0 to 31 db.

Parameters:

power - - new power setting in decibels.

getOutputPower

int getOutputPower()

Answer the radio output power in decibels.

Returns:

- radio output power

turnOffReceiver

void turnOffReceiver()

Turn off the radio receiver

turnOnReceiver

void turnOnReceiver()

Turn on the radio receiver

getIEEEAddress

long getIEEEAddress()

Returns:

the 64-bit IEEE address of this device

turnOnReceiver

void turnOnReceiver(int period)

Turn on the radio receiver for a fixed period

Parameters:

period - in milliseconds

initBaseStation

void initBaseStation()

Used in the host to initialize the base station - a no-op if called on a Spot

closeBaseStation

void closeBaseStation()

Used in the host to close down the base station - a no-op if called on a Spot

isLoggingConnections

boolean isLoggingConnections()

Returns:

true if connection addition and removal is being logged to System.out

setLogConnections

void setLogConnections(boolean logConnections)

Select whether connection addition and removal is being logged to System.out

Parameters:

logConnections - true if connnections should be logged