Diff: RF22Router.h
- Revision:
- 0:e16ffa7cb900
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/RF22Router.h Mon Jul 02 01:29:58 2012 +0000
@@ -0,0 +1,326 @@
+// RF22Router.h
+//
+// Author: Mike McCauley (mikem@open.com.au)
+// Copyright (C) 2011 Mike McCauley
+// $Id: RF22Router.h,v 1.7 2011/02/15 01:18:03 mikem Exp $
+// ported to mbed by Karl Zweimueller
+
+#ifndef RF22Router_h
+#define RF22Router_h
+
+#include <RF22ReliableDatagram.h>
+
+// Default max number of hops we will route
+#define RF22_DEFAULT_MAX_HOPS 30
+
+// The default size of the routing table we keep
+#define RF22_ROUTING_TABLE_SIZE 10
+
+// Error codes
+#define RF22_ROUTER_ERROR_NONE 0
+#define RF22_ROUTER_ERROR_INVALID_LENGTH 1
+#define RF22_ROUTER_ERROR_NO_ROUTE 2
+#define RF22_ROUTER_ERROR_TIMEOUT 3
+#define RF22_ROUTER_ERROR_NO_REPLY 4
+#define RF22_ROUTER_ERROR_UNABLE_TO_DELIVER 5
+
+// This size of RF22_ROUTER_MAX_MESSAGE_LEN is OK for Arduino Mega, but too big for
+// Duemilanova. Size of 50 works with the sample router programs on Duemilanova.
+#define RF22_ROUTER_MAX_MESSAGE_LEN (RF22_MAX_MESSAGE_LEN - sizeof(RF22Router::RoutedMessageHeader))
+//#define RF22_ROUTER_MAX_MESSAGE_LEN 50
+
+// These allow us to define a simulated network topology for testing purposes
+// See RF22Router.cpp for details
+//#define RF22_TEST_NETWORK 1
+//#define RF22_TEST_NETWORK 2
+//#define RF22_TEST_NETWORK 3
+//#define RF22_TEST_NETWORK 4
+
+/////////////////////////////////////////////////////////////////////
+/// \class RF22Router RF22Router.h <RF22Router.h>
+/// \brief RF22 subclass for sending addressed, optionally acknowledged datagrams
+/// multi-hop routed across a network.
+///
+/// Extends RF22ReliableDatagram to define addressed messages
+/// That are reliably transmitted and routed across a network. Each message is transmitted reliably
+/// between each hop in order to get from the source node to the destination node.
+///
+/// With RF22Router, routes are hard wired. This means that each node must have programmed
+/// in it how to reach each of the other nodes it will be trying to communicate with.
+/// This means you must specify the next-hop node address for each of the destination nodes,
+/// using the addRouteTo() function.
+///
+/// When sendtoWait() is called with a new message to deliver, and the destination address,
+/// RF22Router looks up the next hop node for the destination node. It then uses
+/// RF22ReliableDatagram to (reliably) deliver the message to the next hop
+/// (which is expected also to be running an RF22Router). If that next-hop node is not
+/// the final destination, it will also look up the next hop for the destination node and
+/// (reliably) deliver the message to the next hop. By this method, messages can be delivered
+/// across a network of nodes, even if each node cannot hear all of the others in the network.
+/// Each time a message is received for another node and retransmitted to the next hop,
+/// the HOPS filed in teh header is incremented. If a message is received for routing to another node
+/// which has exceed the routers max_hops, the message wioll be dropped and ignored.
+/// This helps prevent infinite routing loops.
+///
+/// RF22Router supports messages with a dest of RF22_BROADCAST_ADDRESS. Such messages are not routed,
+/// and are broadcast (once) to all nodes within range.
+///
+/// The recvfromAck() function is responsible not just for receiving and delivering
+/// messages addressed to this node (or RF22_BROADCAST_ADDRESS), but
+/// it is also responsible for routing other message to their next hop. This means that it is important to
+/// call recvfromAck() or recvfromAckTimeout() frequently in your main loop. recvfromAck() will return
+/// false if it receives a message but it is not for this node.
+///
+/// RF22Router does not provide reliable end-to-end delivery, but uses reliable hop-to-hop delivery.
+/// If a message is unable to be delivered to an end node during to a delivery failure between 2 hops,
+/// the source node will not be told about it.
+///
+/// Note: This class is most useful for networks of nodes that are essentially static
+/// (i.e. the nodes dont move around), and for which the
+/// routing never changes. If that is not the case for your proposed network, see RF22Mesh instead.
+///
+/// \par The Routing Table
+///
+/// The routing table is a local table in RF22Router that holds the information about the next hop node
+/// address for each destination address you may want to send a message to. It is your responsibility
+/// to make sure every node in an RF22Router network has been configured with a unique address and the
+/// routing information so that messages are correctly routed across the network from source node to
+/// destination node. This is usually done once in setup() by calling addRouteTo().
+/// The hardwired routing will in general be different on each node, and will depend on the physical
+/// topololgy of the network.
+/// You can also use addRouteTo() to change a route and
+/// deleteRouteTo() to delete a route at run time. Youcan also clear the entire routing table
+///
+/// The Routing Table has limited capacity for entries (defined by RF22_ROUTING_TABLE_SIZE, which is 10)
+/// if more than RF22_ROUTING_TABLE_SIZE are added, the oldest (first) one will be removed by calling
+/// retireOldestRoute()
+///
+/// \par Message Format
+///
+/// RF22Router add to the lower level RF22ReliableDatagram (and even lower level RF22) class mesage formats.
+/// In those lower level classes, the hop-to-hop message headers are in the RF22 message headers,
+/// and are handled automcatically by tyhe RF22 hardware.
+/// RF22Router and its subclasses add an end-to-end addressing header in the payload of the RF22 message,
+/// and before the RF22Router application data.
+/// - 1 octet DEST, the destination node address (ie the address of the final
+/// destination node for this message)
+/// - 1 octet SOURCE, the source node address (ie the address of the originating node that first sent
+/// the message).
+/// - 1 octet HOPS, the number of hops this message has traversed so far.
+/// - 1 octet ID, an incrementing message ID for end-to-end message tracking for use by subclasses.
+/// Not used by RF22Router.
+/// - 1 octet FLAGS, a bitmask for use by subclasses. Not used by RF22Router.
+/// - 0 or more octets DATA, the application payload data. The length of this data is implicit
+/// in the length of the entire message.
+///
+/// You should be careful to note that there are ID and FLAGS fields in the low level per-hop
+/// message header too. These are used only for hop-to-hop, and in general will be different to
+/// the ones at the RF22Router level.
+///
+/// \par Testing
+///
+/// Bench testing of such networks is notoriously difficult, especially simulating limited radio
+/// connectivity between some nodes.
+/// To assist testing (both during RF22 development and for your own networks)
+/// RF22Router.cpp has the ability to
+/// simulate a number of different small network topologies. Each simulated network supports 4 nodes with
+/// addresses 1 to 4. It operates by pretending to not hear RF22 messages from certain other nodes.
+/// You can enable testing with a \#define TEST_NETWORK in RF22Router.h
+/// The sample programs rf22_mesh_* rely on this feature.
+///
+/// Part of the Arduino RF22 library for operating with HopeRF RF22 compatible transceivers
+/// (see http://www.hoperf.com)
+class RF22Router : public RF22ReliableDatagram
+{
+public:
+
+ /// Defines the structure of the RF22Router message header, used to keep track of end-to-end delivery
+ /// parameters
+ typedef struct
+ {
+ uint8_t dest; ///< Destination node address
+ uint8_t source; ///< Originator node address
+ uint8_t hops; ///< Hops traversed so far
+ uint8_t id; ///< Originator sequence number
+ uint8_t flags; ///< Originator flags
+ // Data follows, Length is implicit in the overall message length
+ } RoutedMessageHeader;
+
+ /// Defines the structure of a RF22Router message
+ typedef struct
+ {
+ RoutedMessageHeader header; ///< end-to-end delivery header
+ uint8_t data[RF22_ROUTER_MAX_MESSAGE_LEN]; ///< Applicaiton payload data
+ } RoutedMessage;
+
+ /// Values for the possible states for routes
+ typedef enum
+ {
+ Invalid = 0, ///< No valid route is known
+ Discovering, ///< Discovering a route (not currently used)
+ Valid ///< Route is valid
+ } RouteState;
+
+ /// Defines an entry in the routing table
+ typedef struct
+ {
+ uint8_t dest; ///< Destination node address
+ uint8_t next_hop; ///< Send via this next hop address
+ uint8_t state; ///< State of this route, one of RouteState
+ } RoutingTableEntry;
+
+ /// Constructor.
+ /// \param[in] thisAddress The address to assign to this node. Defaults to 0
+ /// \param[in] slaveSelectPin the Arduino pin number of the output to use to select the RF22 before
+ /// accessing it
+ /// \param[in] interrupt The interrupt number to use. Default is interrupt 0 (Arduino input pin 2)
+ //RF22Router(uint8_t thisAddress = 0, uint8_t slaveSelectPin = 10, uint8_t interrupt = 0);
+ RF22Router(uint8_t thisAddress ,PinName slaveSelectPin , PinName mosi, PinName miso, PinName sclk, PinName interrupt );
+ /// Initialises this instance and the radio module connected to it.
+ /// Overrides the init() function in RF22.
+ /// Sets max_hops to the default of RF22_DEFAULT_MAX_HOPS (30)
+ boolean init();
+
+ /// Sets the max_hops to the given value
+ /// This controls the maximum number of hops allowed between source and destination nodes
+ /// Messages that are not delivered by the time their HOPS field exceeds max_hops on a
+ /// routing node will be dropped and ignored.
+ /// \param [in] max_hops The new value for max_hops
+ void setMaxHops(uint8_t max_hops);
+
+ /// Adds a route to the local routing table, or updates it if already present.
+ /// If there is not enough room the oldest (first) route will be deleted by calling retireOldestRoute().
+ /// \param [in] dest The destination node address. RF22_BROADCAST_ADDRESS is permitted.
+ /// \param [in] next_hop The address of the next hop to send messages destined for dest
+ /// \param [in] state The satte of the route. Defaults to Valid
+ void addRouteTo(uint8_t dest, uint8_t next_hop, uint8_t state = Valid);
+
+ /// Finds and returns a RoutingTableEntry for the given destination node
+ /// \param [in] dest The desired destination node address.
+ /// \return pointer to a RoutingTableEntry for dest
+ RoutingTableEntry* getRouteTo(uint8_t dest);
+
+ /// Deletes from the local routing table any route for the destination node.
+ /// \param [in] dest The destination node address
+ /// \return true if the route was present
+ boolean deleteRouteTo(uint8_t dest);
+
+ /// Deletes the oldest (first) route from the
+ /// local routing table
+ void retireOldestRoute();
+
+ /// Clears all entries from the
+ /// local routing table
+ void clearRoutingTable();
+
+#ifdef RF22_HAVE_SERIAL
+ /// If RF22_HAVE_SERIAL is defined, this will print out the contents of the local
+ /// routing table using Serial
+ void printRoutingTable();
+#endif
+
+ /// Sends a message to the destination node. Initialises the RF22Router message header
+ /// (the SOURCE address is set to the address of this node, HOPS to 0) and calls
+ /// route() which looks up in the routing table the next hop to deliver to and sends the
+ /// message to the next hop. Waits for an acknowledgement from the next hop
+ /// (but not from the destination node (if that is different).
+ /// \param [in] buf The application message data
+ /// \param [in] len Number of octets in the application message data. 0 is permitted
+ /// \param [in] dest The destination node address
+ /// \return The result code:
+ /// - RF22_ROUTER_ERROR_NONE Message was routed and deliverd to the next hop
+ /// (not necessarily to the final dest address)
+ /// - RF22_ROUTER_ERROR_NO_ROUTE There was no route for dest in the local routing table
+ /// - RF22_ROUTER_ERROR_UNABLE_TO_DELIVER Noyt able to deliver to the next hop
+ /// (usually because it dod not acknowledge due to being off the air or out of range
+ uint8_t sendtoWait(uint8_t* buf, uint8_t len, uint8_t dest);
+
+ /// Similar to sendtoWait() above, but spoofs the source address.
+ /// For internal use only during routing
+ /// \param [in] buf The application message data
+ /// \param [in] len Number of octets in the application message data. 0 is permitted
+ /// \param [in] dest The destination node address
+ /// \param [in] source The (fake) originatong node address.
+ /// \return The result code:
+ /// - RF22_ROUTER_ERROR_NONE Message was routed and deliverd to the next hop
+ /// (not necessarily to the final dest address)
+ /// - RF22_ROUTER_ERROR_NO_ROUTE There was no route for dest in the local routing table
+ /// - RF22_ROUTER_ERROR_UNABLE_TO_DELIVER Noyt able to deliver to the next hop
+ /// (usually because it dod not acknowledge due to being off the air or out of range
+ uint8_t sendtoWait(uint8_t* buf, uint8_t len, uint8_t dest, uint8_t source);
+
+ /// Starts the receiver if it is not running already.
+ /// If there is a valid message available for this node (or RF22_BROADCAST_ADDRESS),
+ /// send an acknowledgement to the last hop
+ /// address (blocking until this is complete), then copy the application message payload data
+ /// to buf and return true
+ /// else return false.
+ /// If a message is copied, *len is set to the length..
+ /// If from is not NULL, the originator SOURCE address is placed in *source.
+ /// If to is not NULL, the DEST address is placed in *dest. This might be this nodes address or
+ /// RF22_BROADCAST_ADDRESS.
+ /// This is the preferred function for getting messages addressed to this node.
+ /// If the message is not a broadcast, acknowledge to the sender before returning.
+ /// \param[in] buf Location to copy the received message
+ /// \param[in,out] len Available space in buf. Set to the actual number of octets copied.
+ /// \param[in] source If present and not NULL, the referenced uint8_t will be set to the SOURCE address
+ /// \param[in] dest If present and not NULL, the referenced uint8_t will be set to the DEST address
+ /// \param[in] id If present and not NULL, the referenced uint8_t will be set to the ID
+ /// \param[in] flags If present and not NULL, the referenced uint8_t will be set to the FLAGS
+ /// (not just those addressed to this node).
+ /// \return true if a valid message was recvived for this node copied to buf
+ boolean recvfromAck(uint8_t* buf, uint8_t* len, uint8_t* source = NULL, uint8_t* dest = NULL, uint8_t* id = NULL, uint8_t* flags = NULL);
+
+ /// Starts the receiver if it is not running already.
+ /// Similar to recvfromAck(), this will block until either a valid message available for this node
+ /// or the timeout expires.
+ /// \param[in] buf Location to copy the received message
+ /// \param[in,out] len Available space in buf. Set to the actual number of octets copied.
+ /// \param[in] timeout Maximum time to wait in milliseconds
+ /// \param[in] source If present and not NULL, the referenced uint8_t will be set to the SOURCE address
+ /// \param[in] dest If present and not NULL, the referenced uint8_t will be set to the DEST address
+ /// \param[in] id If present and not NULL, the referenced uint8_t will be set to the ID
+ /// \param[in] flags If present and not NULL, the referenced uint8_t will be set to the FLAGS
+ /// (not just those addressed to this node).
+ /// \return true if a valid message was copied to buf
+ boolean recvfromAckTimeout(uint8_t* buf, uint8_t* len, uint16_t timeout, uint8_t* source = NULL, uint8_t* dest = NULL, uint8_t* id = NULL, uint8_t* flags = NULL);
+
+protected:
+
+ /// Lets sublasses peek at messages going
+ /// past before routing or local delivery.
+ /// Called by recvfromAck() immediately after it gets the message from RF22ReliableDatagram
+ /// \param [in] message Pointer to the RF22Router message that was received.
+ /// \param [in] messageLen Length of message in octets
+ virtual void peekAtMessage(RoutedMessage* message, uint8_t messageLen);
+
+ /// Finds the next-hop route and sends the message via RF22ReliableDatagram::sendtoWait().
+ /// This is virtual, which lets subclasses override or intercept the route() function.
+ /// Called by sendtoWait after the message header has been filled in.
+ /// \param [in] message Pointer to the RF22Router message to be sent.
+ /// \param [in] messageLen Length of message in octets
+ virtual uint8_t route(RoutedMessage* message, uint8_t messageLen);
+
+ /// Deletes a specific rout entry from therouting table
+ /// \param [in] index The 0 based index of the routing table entry to delete
+ void deleteRoute(uint8_t index);
+
+ /// The last end-to-end sequence number to be used
+ /// Defaults to 0
+ uint8_t _lastE2ESequenceNumber;
+
+ /// The maximum number of hops permitted in routed messages.
+ /// If a routed message would exceed this number of hops it is dropped and ignored.
+ uint8_t _max_hops;
+
+private:
+
+ /// Temporary mesage buffer
+ static RoutedMessage _tmpMessage;
+
+ /// Local routing table
+ RoutingTableEntry _routes[RF22_ROUTING_TABLE_SIZE];
+};
+
+#endif
+
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