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#include <wl_token_ring.h> |
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|
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#include <stdlib.h> |
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#include <stdio.h> |
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|
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#include <wl_defs.h> |
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#include <wireless.h> |
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#include <sensor_matrix.h> |
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#include <queue.h> |
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|
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#ifdef ROBOT
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#ifndef FIREFLY
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#include <bom.h> |
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#endif
|
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#include <time.h> |
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#endif
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|
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#define DEFAULT_SENSOR_MATRIX_SIZE 20 |
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|
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/*Ring States*/
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|
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#define NONMEMBER 0 |
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#define MEMBER 1 |
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#define JOINING 2 |
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#define ACCEPTED 3 |
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#define LEAVING 4 |
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|
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/*Frame Types*/
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#define TOKEN_JOIN_ACCEPT_FRAME 1 |
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|
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/*Function Prototypes*/
|
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|
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/*Wireless Library Prototypes*/
|
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void wl_token_ring_timeout_handler(void); |
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void wl_token_ring_response_handler(int frame, int received); |
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void wl_token_ring_receive_handler(char type, int source, unsigned char* packet, |
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int length);
|
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void wl_token_ring_cleanup(void); |
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|
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/*Helper Functions*/
|
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void wl_token_pass_token(void); |
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int get_token_distance(int robot1, int robot2); |
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void wl_token_get_token(void); |
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|
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/*Packet Handling Routines*/
|
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void wl_token_pass_receive(int source, char nextRobot, unsigned char* sensorData, int sensorDataLength); |
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void wl_token_interrupt_request_receive(int source, int robot); |
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void wl_token_interrupt_pass_receive(int source, int robot); |
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void wl_token_bom_on_receive(int source); |
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void wl_token_join_receive(int source); |
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void wl_token_join_accept_receive(int source); |
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|
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/*Global Variables*/
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|
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//the sensor matrix
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SensorMatrix* sensorMatrix; |
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|
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//the robot we are waiting to say it has received the token. -1 if unspecified
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int wl_token_next_robot = -1; |
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|
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//true if the robot should be in the token ring, 0 otherwise
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int ringState = NONMEMBER;
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//the id of the robot who accepted us into the token ring, only used in ACCEPTED state
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int acceptor = -1; |
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//id of the robot we are accepting
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int accepted = -1; |
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|
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//the counter for when we assume a robot is dead
|
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int deathDelay = -1; |
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//the counter for joining, before we form our own token ring
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int joinDelay = -1; |
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//queue containing ids of interruption requests
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Queue* interrupting = NULL;
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|
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//current robot to check in the iterator
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int iteratorCount = 0; |
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|
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void do_nothing(void) {} |
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int get_nothing(void) {return -1;} |
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|
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#ifdef ROBOT
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#ifndef FIREFLY
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void (*bom_on_function) (void) = bom_on; |
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void (*bom_off_function) (void) = bom_off; |
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int (*get_max_bom_function) (void) = get_max_bom; |
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#else
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void (*bom_on_function) (void) = do_nothing; |
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void (*bom_off_function) (void) = do_nothing; |
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int (*get_max_bom_function) (void) = get_nothing; |
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#endif
|
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#else
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void (*bom_on_function) (void) = do_nothing; |
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void (*bom_off_function) (void) = do_nothing; |
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int (*get_max_bom_function) (void) = get_nothing; |
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#endif
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|
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PacketGroupHandler wl_token_ring_handler = |
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{WL_TOKEN_RING_GROUP, wl_token_ring_timeout_handler, |
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wl_token_ring_response_handler, wl_token_ring_receive_handler, |
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wl_token_ring_cleanup}; |
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|
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/**
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* Initialize the token ring packet group and register it with the
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* wireless library. The robot will not join a token ring.
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**/
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void wl_token_ring_register()
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{ |
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if (wl_get_xbee_id() > 0xFF) |
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{ |
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//Note: if this becomes an issue (unlikely), we could limit sensor information
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//to half a byte and use 12 bits for the id
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WL_DEBUG_PRINT("XBee ID must be single byte for token ring, is ");
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WL_DEBUG_PRINT_INT(wl_get_xbee_id()); |
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WL_DEBUG_PRINT(".\r\n");
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return;
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} |
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sensorMatrix = sensor_matrix_create(); |
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interrupting = queue_create(); |
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//add ourselves to the sensor matrix
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sensor_matrix_set_in_ring(sensorMatrix, wl_get_xbee_id(), 0);
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wl_register_packet_group(&wl_token_ring_handler); |
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} |
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|
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/**
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* Removes the packet group from the wireless library.
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**/
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void wl_token_ring_unregister()
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{ |
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wl_unregister_packet_group(&wl_token_ring_handler); |
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} |
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|
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/**
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* Sets the functions that are called when the BOM ought to be
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* turned on or off. This could be used for things such as
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* charging stations, which have multiple BOMs.
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*
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* @param on_function the function to be called when the BOM
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* should be turned on
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* @param off_function the function to be called when the BOM
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* should be turned off
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* @param max_bom_function the function to be called when a
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* measurement of the maximum BOM reading is needed.
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**/
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void wl_token_ring_set_bom_functions(void (*on_function) (void), |
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void (*off_function) (void), int (*max_bom_function) (void)) |
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{ |
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bom_on_function = on_function; |
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bom_off_function = off_function; |
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get_max_bom_function = max_bom_function; |
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} |
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|
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/**
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* Called to cleanup the token ring packet group.
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**/
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void wl_token_ring_cleanup()
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{ |
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sensor_matrix_destroy(sensorMatrix); |
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queue_destroy(interrupting); |
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} |
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|
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/**
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* Called approximately every quarter second by the wireless library.
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**/
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void wl_token_ring_timeout_handler()
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{ |
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//someone is not responding, assume they are dead
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if (deathDelay == 0) |
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{ |
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//pass the token to the next robot if we think someone has died
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//also, declare that person dead, as long as it isn't us
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if (wl_token_next_robot != wl_get_xbee_id())
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{ |
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sensor_matrix_set_in_ring(sensorMatrix, wl_token_next_robot, 0);
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WL_DEBUG_PRINT("Robot ");
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WL_DEBUG_PRINT_INT(wl_token_next_robot); |
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WL_DEBUG_PRINT(" has died.\r\n");
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} |
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|
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// we may have been dropped from the ring when this is received
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if (ringState == MEMBER)
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wl_token_pass_token(); |
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} |
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|
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//we must start our own token ring, no one is responding to us
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if (joinDelay == 0) |
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{ |
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if (sensor_matrix_get_joined(sensorMatrix) == 0) |
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{ |
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WL_DEBUG_PRINT("Creating our own token ring, no robots seem to exist.\r\n");
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sensor_matrix_set_in_ring(sensorMatrix, wl_get_xbee_id(), 1);
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ringState = MEMBER; |
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//this will make us pass the token to ourself
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//repeatedly, and other robots when they join
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deathDelay = DEATH_DELAY; |
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wl_token_next_robot = wl_get_xbee_id(); |
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} |
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else
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{ |
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WL_DEBUG_PRINT("Attempting to join the token ring again.\r\n");
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//attempt to rejoin with a random delay
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wl_token_ring_join(); |
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joinDelay = rand() / (RAND_MAX / JOIN_DELAY) + 1;
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} |
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} |
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if (deathDelay >= 0) |
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deathDelay--; |
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if (joinDelay >= 0) |
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joinDelay--; |
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} |
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|
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/**
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* Called when the XBee tells us if a packet we sent has been received.
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*
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* @param frame the frame number assigned when the packet was sent
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* @param received 1 if the packet was received, 0 otherwise
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**/
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void wl_token_ring_response_handler(int frame, int received) |
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{ |
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if (!received)
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{ |
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WL_DEBUG_PRINT("FAILED.\r\n");
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} |
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} |
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|
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/**
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* Called when we recieve a token ring packet.
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* @param type the type of the packet
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* @param source the id of the robot who sent the packet
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* @param packet the data in the packet
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* @param length the length of the packet in bytes
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**/
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void wl_token_ring_receive_handler(char type, int source, unsigned char* packet, |
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int length)
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{ |
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switch (type)
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{ |
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case WL_TOKEN_PASS:
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if (length < 1) |
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{ |
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WL_DEBUG_PRINT("Malformed Token Pass packet received.\r\n");
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return;
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} |
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wl_token_pass_receive(source, packet[0], packet + 1, length - 1); |
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break;
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case WL_TOKEN_BOM_ON:
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//add the robot to the sensor matrix if it is not already there
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wl_token_bom_on_receive(source); |
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break;
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case WL_TOKEN_INTERRUPT_REQUEST:
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wl_token_interrupt_request_receive(source, packet[0]);
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break;
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case WL_TOKEN_INTERRUPT_PASS:
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wl_token_interrupt_pass_receive(source, packet[0]);
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break;
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case WL_TOKEN_JOIN:
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wl_token_join_receive(source); |
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break;
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case WL_TOKEN_JOIN_ACCEPT:
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wl_token_join_accept_receive(source); |
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break;
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default:
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WL_DEBUG_PRINT("Unimplemented token ring packet received.\r\n");
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break;
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} |
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} |
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|
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/**
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* Causes the robot to join an existing token ring, or create one
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* if no token ring exists. The token ring uses global and robot to robot
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* packets, and does not rely on any PAN.
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**/
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void wl_token_ring_join()
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{ |
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WL_DEBUG_PRINT("Joining the token ring.\r\n");
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ringState = JOINING; |
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joinDelay = JOIN_DELAY; |
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wl_send_global_packet(WL_TOKEN_RING_GROUP, WL_TOKEN_JOIN, |
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NULL, 0, 0); |
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} |
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|
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/**
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* Causes the robot to leave the token ring. The robot stops
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* alerting others of its location, but continues storing the
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* locations of other robots.
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**/
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void wl_token_ring_leave()
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{ |
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ringState = LEAVING; |
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} |
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|
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/**
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* Requests that the specified robot be given the token and
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* allowed to flash its BOM. After its BOM is flashed, the
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* token will return to the robot who sent it.
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*
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* @param robot the ID of the robot which should flash its BOM
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**/
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void wl_token_request(int robot) |
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{ |
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char buf[1]; |
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buf[0] = robot;
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wl_send_global_packet(WL_TOKEN_RING_GROUP, WL_TOKEN_INTERRUPT_REQUEST, |
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buf, 1, 0); |
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} |
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|
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/**
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* Returns the BOM reading robot source has for robot dest.
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*
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* @param source the robot that made the BOM reading
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* @param dest the robot whose relative location is returned
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*
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* @return a BOM reading from robot source to robot dest,
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* in the range 0-15, or -1 if it is unknown
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**/
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int wl_token_get_sensor_reading(int source, int dest) |
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{ |
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return sensor_matrix_get_reading(sensorMatrix, source, dest);
|
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} |
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|
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/**
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* Returns the BOM reading we have for robot dest.
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*
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* @param dest the robot whose relative location is returned
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*
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* @return a BOM reading from us to robot dest, in the range
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* 0-15, or -1 if it is unkown
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**/
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int wl_token_get_my_sensor_reading(int dest) |
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{ |
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return wl_token_get_sensor_reading(wl_get_xbee_id(), dest);
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} |
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|
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/**
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* This method is called when we receive a token pass packet.
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* @param source is the robot it came from
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* @param nextRobot is the robot the token was passed to
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* @param sensorData a char with an id followed by a char with the sensor
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* reading for that robot, repeated for sensorDataLength bytes
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* @param sensorDataLength the length in bytes of sensorData
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*/
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void wl_token_pass_receive(int source, char nextRobot, unsigned char* sensorData, int sensorDataLength) |
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{ |
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int i, j;
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deathDelay = -1;
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|
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WL_DEBUG_PRINT("Received the token, next robot is ");
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WL_DEBUG_PRINT_INT((int)nextRobot);
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WL_DEBUG_PRINT(" \r\n");
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sensor_matrix_set_in_ring(sensorMatrix, source, 1);
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|
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//with this packet, we are passed the id of the next robot in the ring
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//and the sensor matrix, a list of id and sensor reading pairs (two bytes for both)
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j = 0;
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for (i = 0; i < sensor_matrix_get_size(sensorMatrix); i++) |
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{ |
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if (i == source)
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continue;
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|
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//set the sensor information we receive
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if (j < sensorDataLength / 2 && sensorData[2 * j] == i) |
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{ |
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//the robot we were going to accept has already been accepted
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if (accepted == i)
|
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{ |
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accepted = -1;
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WL_DEBUG_PRINT("Someone accepted the robot we did.\r\n");
|
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} |
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sensor_matrix_set_reading(sensorMatrix, source, i, |
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sensorData[2 * j + 1]); |
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sensor_matrix_set_in_ring(sensorMatrix, i, 1);
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j++; |
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} |
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else
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{ |
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if (sensor_matrix_get_in_ring(sensorMatrix, i))
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{ |
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WL_DEBUG_PRINT("Robot ");
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WL_DEBUG_PRINT_INT(i); |
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WL_DEBUG_PRINT(" has been removed from the sensor matrix of robot ");
|
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WL_DEBUG_PRINT_INT(wl_get_xbee_id()); |
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WL_DEBUG_PRINT(" due to a packet from robot ");
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WL_DEBUG_PRINT_INT(source); |
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WL_DEBUG_PRINT(".\r\n");
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sensor_matrix_set_in_ring(sensorMatrix, i, 0);
|
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} |
389 |
|
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if (i == wl_get_xbee_id() && ringState == MEMBER)
|
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{ |
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ringState = NONMEMBER; |
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wl_token_ring_join(); |
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|
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WL_DEBUG_PRINT("We have been removed from the ring ");
|
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WL_DEBUG_PRINT("and are rejoining.\r\n");
|
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} |
398 |
|
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//the person who accepted us is dead... let's ask again
|
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if (i == acceptor)
|
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{ |
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sensor_matrix_set_in_ring(sensorMatrix, |
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wl_get_xbee_id(), 1);
|
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ringState = NONMEMBER; |
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acceptor = -1;
|
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wl_token_ring_join(); |
407 |
} |
408 |
} |
409 |
} |
410 |
|
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wl_token_next_robot = nextRobot; |
412 |
|
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deathDelay = get_token_distance(wl_get_xbee_id(), nextRobot) * DEATH_DELAY; |
414 |
|
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//we have the token
|
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if (wl_token_next_robot == wl_get_xbee_id())
|
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wl_token_get_token(); |
418 |
} |
419 |
|
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/**
|
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* Gets the distance in the token ring between two robots.
|
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*
|
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* @param robot1 the first robot
|
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* @param robot2 the second robot
|
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*
|
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* @return the number of passes before the token is expected
|
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* to reach robot2 from robot1
|
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**/
|
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int get_token_distance(int robot1, int robot2) |
430 |
{ |
431 |
int curr = robot1 + 1; |
432 |
int count = 1; |
433 |
while (1) |
434 |
{ |
435 |
if (curr == sensor_matrix_get_size(sensorMatrix))
|
436 |
curr = 0;
|
437 |
if (curr == robot2)
|
438 |
break;
|
439 |
if (sensor_matrix_get_in_ring(sensorMatrix, curr))
|
440 |
count++; |
441 |
curr++; |
442 |
} |
443 |
return count;
|
444 |
} |
445 |
|
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/**
|
447 |
* Passes the token to the next robot in the token ring.
|
448 |
**/
|
449 |
void wl_token_pass_token()
|
450 |
{ |
451 |
char nextRobot;
|
452 |
int i = wl_get_xbee_id() + 1; |
453 |
if (accepted == -1) |
454 |
{ |
455 |
while (1) |
456 |
{ |
457 |
if (i == sensor_matrix_get_size(sensorMatrix))
|
458 |
i = 0;
|
459 |
if (sensor_matrix_get_in_ring(sensorMatrix, i))
|
460 |
{ |
461 |
nextRobot = (char)i;
|
462 |
break;
|
463 |
} |
464 |
i++; |
465 |
} |
466 |
} |
467 |
else
|
468 |
{ |
469 |
WL_DEBUG_PRINT("Accepting new robot, sending it the token.\r\n");
|
470 |
//add a new robot to the token ring
|
471 |
sensor_matrix_set_in_ring(sensorMatrix, accepted, 1);
|
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nextRobot = accepted; |
473 |
accepted = -1;
|
474 |
} |
475 |
|
476 |
//we don't include ourself
|
477 |
int packetSize = 1 + 2 * (sensor_matrix_get_joined(sensorMatrix) - 1); |
478 |
char* buf = (char*)malloc(packetSize * sizeof(char)); |
479 |
if (!buf)
|
480 |
{ |
481 |
WL_DEBUG_PRINT_INT(packetSize); |
482 |
WL_DEBUG_PRINT("Out of memory - pass token.\r\n");
|
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return;
|
484 |
} |
485 |
buf[0] = nextRobot;
|
486 |
|
487 |
int j = 0; |
488 |
for (i = 0; i < sensor_matrix_get_size(sensorMatrix); i++) |
489 |
if (sensor_matrix_get_in_ring(sensorMatrix, i) && i != wl_get_xbee_id())
|
490 |
{ |
491 |
buf[2*j + 1] = i; |
492 |
buf[2*j + 2] = sensor_matrix_get_reading(sensorMatrix, wl_get_xbee_id(), i); |
493 |
j++; |
494 |
} |
495 |
|
496 |
WL_DEBUG_PRINT("Passing the token to robot ");
|
497 |
WL_DEBUG_PRINT_INT(buf[0]);
|
498 |
WL_DEBUG_PRINT(".\r\n");
|
499 |
wl_send_global_packet(WL_TOKEN_RING_GROUP, WL_TOKEN_PASS, |
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buf, packetSize, 3);
|
501 |
|
502 |
wl_token_next_robot = nextRobot; |
503 |
deathDelay = DEATH_DELAY; |
504 |
free(buf); |
505 |
} |
506 |
|
507 |
/**
|
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* Called when a packet is received stating that another robot has turned
|
509 |
* its BOM on. Our BOM is then read, and the data is added to the sensor
|
510 |
* matrix.
|
511 |
*
|
512 |
* @param source the robot whose BOM is on
|
513 |
**/
|
514 |
void wl_token_bom_on_receive(int source) |
515 |
{ |
516 |
WL_DEBUG_PRINT("Robot ");
|
517 |
WL_DEBUG_PRINT_INT(source); |
518 |
WL_DEBUG_PRINT(" has flashed its bom.\r\n");
|
519 |
sensor_matrix_set_reading(sensorMatrix, wl_get_xbee_id(), |
520 |
source, get_max_bom_function()); |
521 |
} |
522 |
|
523 |
/**
|
524 |
* This method is called when we receive the token. Upon receiving
|
525 |
* the token, we must send a BOM_ON packet, flash the BOM, and send
|
526 |
* the token to the next robot.
|
527 |
*
|
528 |
* If there is a pending request for the token, this is processed first.
|
529 |
**/
|
530 |
void wl_token_get_token()
|
531 |
{ |
532 |
WL_DEBUG_PRINT("We have the token.\r\n");
|
533 |
if (ringState == ACCEPTED)
|
534 |
{ |
535 |
sensor_matrix_set_in_ring(sensorMatrix, |
536 |
wl_get_xbee_id(), 1);
|
537 |
WL_DEBUG_PRINT("Now a member of the token ring.\r\n");
|
538 |
ringState = MEMBER; |
539 |
} |
540 |
|
541 |
if (ringState == LEAVING || ringState == NONMEMBER)
|
542 |
{ |
543 |
sensor_matrix_set_in_ring(sensorMatrix, wl_get_xbee_id(), 0);
|
544 |
if (ringState == NONMEMBER)
|
545 |
{ |
546 |
WL_DEBUG_PRINT("We should have left the token ring, but didn't.\r\n");
|
547 |
} |
548 |
return;
|
549 |
} |
550 |
|
551 |
//check for interruption requests
|
552 |
if (queue_size(interrupting) > 0) |
553 |
{ |
554 |
char buf[1]; |
555 |
buf[0] = (char)(int)queue_remove(interrupting); |
556 |
|
557 |
//in case this robot has requested multiple times
|
558 |
queue_remove_all(interrupting, (void*)(int)buf[0]); |
559 |
|
560 |
wl_send_global_packet(WL_TOKEN_RING_GROUP, WL_TOKEN_INTERRUPT_PASS, |
561 |
buf, 1, 0); |
562 |
|
563 |
deathDelay = DEATH_DELAY; |
564 |
wl_token_next_robot = buf[0];
|
565 |
return;
|
566 |
} |
567 |
|
568 |
WL_DEBUG_PRINT("Our BOM has been flashed.\r\n");
|
569 |
wl_send_global_packet(WL_TOKEN_RING_GROUP, WL_TOKEN_BOM_ON, |
570 |
NULL, 0, 0); |
571 |
|
572 |
bom_on_function(); |
573 |
#ifdef ROBOT
|
574 |
delay_ms(BOM_DELAY); |
575 |
#endif
|
576 |
bom_off_function(); |
577 |
|
578 |
if (!sensor_matrix_get_in_ring(sensorMatrix, wl_get_xbee_id()))
|
579 |
{ |
580 |
WL_DEBUG_PRINT("Removed from sensor matrix while flashing BOM.\r\n");
|
581 |
} |
582 |
|
583 |
wl_token_pass_token(); |
584 |
} |
585 |
|
586 |
/**
|
587 |
* Called when a request to join the token ring is received.
|
588 |
* If we are the robot preceding the requester in the ring,
|
589 |
* we respond with a JOIN_ACCEPT packet and pass the token to
|
590 |
* this robot when we receive the token.
|
591 |
*
|
592 |
* @param source the robot who requested to join
|
593 |
**/
|
594 |
void wl_token_join_receive(int source) |
595 |
{ |
596 |
WL_DEBUG_PRINT("Received joining request from robot ");
|
597 |
WL_DEBUG_PRINT_INT(source); |
598 |
WL_DEBUG_PRINT(".\r\n");
|
599 |
|
600 |
//we cannot accept the request if we are not a member
|
601 |
if (ringState != MEMBER)
|
602 |
return;
|
603 |
//if they didn't get our response, see if we should respond again
|
604 |
if (accepted == source)
|
605 |
accepted = -1;
|
606 |
//we can only accept one request at a time
|
607 |
if (accepted != -1) |
608 |
return;
|
609 |
|
610 |
//check if we are the preceding robot in the token ring
|
611 |
int i = source - 1; |
612 |
while (1) |
613 |
{ |
614 |
if (i < 0) |
615 |
i = sensor_matrix_get_size(sensorMatrix) - 1;
|
616 |
//we must send a join acceptance
|
617 |
if (i == wl_get_xbee_id())
|
618 |
break;
|
619 |
|
620 |
//another robot will handle it
|
621 |
if (sensor_matrix_get_in_ring(sensorMatrix, i))
|
622 |
return;
|
623 |
i--; |
624 |
} |
625 |
|
626 |
accepted = source; |
627 |
wl_send_robot_to_robot_global_packet(WL_TOKEN_RING_GROUP, WL_TOKEN_JOIN_ACCEPT, |
628 |
NULL, 0, source, TOKEN_JOIN_ACCEPT_FRAME); |
629 |
|
630 |
WL_DEBUG_PRINT("Accepting robot ");
|
631 |
WL_DEBUG_PRINT_INT(source); |
632 |
WL_DEBUG_PRINT(" into the token ring.\r\n");
|
633 |
|
634 |
joinDelay = -1;
|
635 |
|
636 |
// the token ring has not started yet
|
637 |
if (sensor_matrix_get_joined(sensorMatrix) == 1) |
638 |
wl_token_pass_token(); |
639 |
} |
640 |
|
641 |
/**
|
642 |
* Called when we receive a JOIN_ACCEPT packet in attempting to join
|
643 |
* the token ring.
|
644 |
* Our attempt to join the ring is stopped, and we wait for the token.
|
645 |
*
|
646 |
* @param source the robot who accepted us
|
647 |
**/
|
648 |
void wl_token_join_accept_receive(int source) |
649 |
{ |
650 |
WL_DEBUG_PRINT("Accepted into the token ring by robot ");
|
651 |
WL_DEBUG_PRINT_INT(source); |
652 |
WL_DEBUG_PRINT(".\r\n");
|
653 |
joinDelay = -1;
|
654 |
ringState = ACCEPTED; |
655 |
acceptor = source; |
656 |
|
657 |
//add ourselves to the token ring
|
658 |
sensor_matrix_set_in_ring(sensorMatrix, wl_get_xbee_id(), 1);
|
659 |
} |
660 |
|
661 |
/**
|
662 |
* Called when we receive a packet passing the token and interrupting
|
663 |
* the token ring.
|
664 |
* If the token has been passed to us, we flash our BOM
|
665 |
* and pass it back.
|
666 |
*
|
667 |
* @param source the robot who sent the interrupt packet
|
668 |
* @param robot the robot the token has been passed to
|
669 |
**/
|
670 |
void wl_token_interrupt_pass_receive(int source, int robot) |
671 |
{ |
672 |
if (wl_get_xbee_id() != robot)
|
673 |
{ |
674 |
queue_remove_all(interrupting, (void*)robot);
|
675 |
wl_token_next_robot = robot; |
676 |
deathDelay = DEATH_DELAY + rand() / (RAND_MAX / (2 * DEATH_DELAY));
|
677 |
return;
|
678 |
} |
679 |
wl_send_global_packet(WL_TOKEN_RING_GROUP, WL_TOKEN_BOM_ON, |
680 |
NULL, 0, 0); |
681 |
|
682 |
bom_on_function(); |
683 |
#ifdef ROBOT
|
684 |
delay_ms(BOM_DELAY); |
685 |
#endif
|
686 |
bom_off_function(); |
687 |
|
688 |
//we don't include ourself, only if we are in the ring
|
689 |
int packetSize = 1 + 2 * (sensor_matrix_get_joined(sensorMatrix) - 1); |
690 |
if (!sensor_matrix_get_in_ring(sensorMatrix, wl_get_xbee_id()))
|
691 |
packetSize += 2;
|
692 |
char* buf = (char*)malloc(packetSize * sizeof(char)); |
693 |
if (!buf)
|
694 |
{ |
695 |
WL_DEBUG_PRINT("Out of memory - pass_receive.\r\n");
|
696 |
return;
|
697 |
} |
698 |
|
699 |
//return the token to where we got it from
|
700 |
buf[0] = source;
|
701 |
|
702 |
int i = 0, j = 0; |
703 |
for (i = 0; i < sensor_matrix_get_size(sensorMatrix); i++) |
704 |
if (sensor_matrix_get_in_ring(sensorMatrix, i) && i != wl_get_xbee_id())
|
705 |
{ |
706 |
buf[2*j + 1] = i; |
707 |
buf[2*j + 2] = sensor_matrix_get_reading(sensorMatrix, wl_get_xbee_id(), i); |
708 |
j++; |
709 |
} |
710 |
|
711 |
wl_send_global_packet(WL_TOKEN_RING_GROUP, WL_TOKEN_PASS, |
712 |
buf, packetSize, 0);
|
713 |
|
714 |
wl_token_next_robot = source; |
715 |
deathDelay = DEATH_DELAY; |
716 |
free(buf); |
717 |
} |
718 |
|
719 |
/**
|
720 |
* Returns the number of robots in the token ring.
|
721 |
*
|
722 |
* @return the number of robots in the token ring
|
723 |
**/
|
724 |
int wl_token_get_robots_in_ring(void) |
725 |
{ |
726 |
return sensor_matrix_get_joined(sensorMatrix);
|
727 |
} |
728 |
|
729 |
/**
|
730 |
* Returns true if the specified robot is in the token ring, false
|
731 |
* otherwise.
|
732 |
*
|
733 |
* @param robot the robot to check for whether it is in the token ring
|
734 |
* @return nonzero if the robot is in the token ring, zero otherwise
|
735 |
**/
|
736 |
int wl_token_is_robot_in_ring(int robot) |
737 |
{ |
738 |
return sensor_matrix_get_in_ring(sensorMatrix, robot);
|
739 |
} |
740 |
|
741 |
/**
|
742 |
* Begins iterating through the robots in the token ring.
|
743 |
*
|
744 |
* @see wl_token_iterator_has_next, wl_token_iterator_next
|
745 |
**/
|
746 |
void wl_token_iterator_begin(void) |
747 |
{ |
748 |
int i = 0; |
749 |
iteratorCount = 0;
|
750 |
while (!sensor_matrix_get_in_ring(sensorMatrix, i) &&
|
751 |
i < sensor_matrix_get_size(sensorMatrix)) |
752 |
i++; |
753 |
if (i == sensor_matrix_get_size(sensorMatrix))
|
754 |
i = -1;
|
755 |
iteratorCount = i; |
756 |
} |
757 |
|
758 |
/**
|
759 |
* Returns true if there are more robots in the token ring
|
760 |
* to iterate through, and false otherwise.
|
761 |
*
|
762 |
* @return nonzero if there are more robots to iterate through,
|
763 |
* zero otherwise
|
764 |
*
|
765 |
* @see wl_token_iterator_begin, wl_token_iterator_next
|
766 |
**/
|
767 |
int wl_token_iterator_has_next(void) |
768 |
{ |
769 |
return iteratorCount != -1; |
770 |
} |
771 |
|
772 |
/**
|
773 |
* Returns the next robot ID in the token ring.
|
774 |
*
|
775 |
* @return the next robot ID in the token ring, or -1 if none exists
|
776 |
*
|
777 |
* @see wl_token_iterator_begin, wl_token_iterator_has_next
|
778 |
**/
|
779 |
int wl_token_iterator_next(void) |
780 |
{ |
781 |
int result = iteratorCount;
|
782 |
if (result < 0) |
783 |
return result;
|
784 |
|
785 |
iteratorCount++; |
786 |
while (!sensor_matrix_get_in_ring(sensorMatrix, iteratorCount) &&
|
787 |
iteratorCount < sensor_matrix_get_size(sensorMatrix)) |
788 |
iteratorCount++; |
789 |
if (iteratorCount == sensor_matrix_get_size(sensorMatrix))
|
790 |
iteratorCount = -1;
|
791 |
return result;
|
792 |
} |
793 |
|
794 |
/**
|
795 |
* Called when we receive a request to interrupt the token ring.
|
796 |
* We add the robot to our list of interrupt requests,
|
797 |
* and will send the token to this robot when we next receive the
|
798 |
* token, unless someone else does so first.
|
799 |
*
|
800 |
* @param source the robot requesting interruption
|
801 |
* @param robt the robot requested to interrupt the token ring
|
802 |
**/
|
803 |
void wl_token_interrupt_request_receive(int source, int robot) |
804 |
{ |
805 |
queue_add(interrupting, (void*)robot);
|
806 |
} |
807 |
|
808 |
int wl_token_get_num_robots(void){ |
809 |
return sensor_matrix_get_joined(sensorMatrix);
|
810 |
} |
811 |
|
812 |
int wl_token_get_matrix_size(void){ |
813 |
return sensor_matrix_get_size(sensorMatrix);
|
814 |
} |