/trunk/code/lib/src/libwireless/xbee.c - Diff - Colony - Robotics Club

Revision 336

Updated wireless to use a circular buffer instead of a queue using malloc. Tested on both the computer and robots with a token ring, and was successful.

     #include <unistd.h>
     #include <pthread.h>
     #include <errno.h>
     #include <termios.h>
     #else
-...
     #include <stdlib.h>
     #include <string.h>
     #include <queue.h>
     #define XBEE_FRAME_START 0x7E
     /*Frame Types*/
-...
     void xbee_enter_command_mode(void);
     void xbee_exit_command_mode(void);
     void xbee_enter_api_mode(void);
     void xbee_exit_api_mode(void);
     void xbee_wait_for_string(char* s, int len);
     void xbee_wait_for_ok(void);
-...
     /*Global Variables*/
     #ifndef ROBOT
     char* xbee_com_port;
     char* xbee_com_port = XBEE_PORT_DEFAULT;
     int xbee_stream;
     pthread_t* xbee_listen_thread;
     #endif
     Queue* xbee_queue;
     // TODO: is this a good size?
     #define XBEE_BUFFER_SIZE	256
     // a buffer for data received from the XBee
     char arrival_buf[XBEE_BUFFER_SIZE];
     // location of last unread byte in buffer
     volatile int buffer_last = 0;
     // first unread byte in buffer
     volatile int buffer_first = 0;
     //used to store packets as they are read
     char xbee_buf[128];
     int currentBufPos = 0;
-...
     /**
      * Interrupt for the robot. Adds bytes received from the xbee
      * to the queue.
      * to the buffer.
      **/
     #ifndef FIREFLY
     ISR(USART1_RX_vect)
+    {
     	char c = UDR1;
     	queue_add(xbee_queue, (void*)(int)c);
     	arrival_buf[buffer_last] = c;
     	int t = buffer_last + 1;
     	if (t == XBEE_BUFFER_SIZE)
     		t = 0;
     	if (t == buffer_first)
+    	{
     		WL_DEBUG_PRINT("Out of space in buffer.\n");
+    	}
     	buffer_last = t;
+    }
     #else
     SIGNAL(SIG_USART0_RECV)
+    {
     	char c = UDR0;
     	queue_add(xbee_queue, (void*)(int)c);
     	arrival_buf[buffer_last] = c;
     	int t = buffer_last + 1;
     	if (t == XBEE_BUFFER_SIZE)
     		t = 0;
     	if (t == buffer_first)
+    	{
     		WL_DEBUG_PRINT("Out of space in buffer.\n");
+    	}
     	buffer_last = t;
+    }
     #endif
-...
     	while (1)
+    	{
     		xbee_read(&c, 1);
     		queue_add(xbee_queue, (void*)(int)c);
     		arrival_buf[buffer_last] = c;
     		int t = buffer_last + 1;
     		if (t == XBEE_BUFFER_SIZE)
     			t = 0;
     		if (t == buffer_first)
+    		{
     			WL_DEBUG_PRINT("Out of space in buffer.\n");
+    		}
     		buffer_last = t;
+    	}
     	return 0;
+    }
-...
     /**
      * Initializes the XBee library so that other functions may be used.
      **/
     void xbee_lib_init(void)
     int xbee_lib_init(void)
+    {
     	xbee_queue = queue_create();
     	arrival_buf[0] = 'A';
     	arrival_buf[1] = 'A';
     	arrival_buf[2] = 'A';
     	#ifdef ROBOT
     	//enable the receiving interrupt
-...
     	#endif
     	sei();
     	#else
     	printf("Connecting to port %s.\n", xbee_com_port);
     	xbee_stream = open(xbee_com_port, O_RDWR);
     	if (xbee_stream == -1 || lockf(xbee_stream, F_TEST, 0) != 0)
     		xbee_stream = open(XBEE_PORT2, O_RDWR);
     	if (xbee_stream == -1 || lockf(xbee_stream, F_TEST, 0) != 0)
     	if (xbee_stream == -1/* || lockf(xbee_stream, F_TEST, 0) != 0*/)
+    	{
     		printf("Failed to open connection to XBee on port %s\r\n",xbee_com_port);
     		exit(0);
     		printf("Failed to open connection to XBee on port %s\r\n", xbee_com_port);
     		return -1;
+    	}
     	lockf(xbee_stream, F_LOCK, 0);
     	// set baud rate, etc. correctly
     	struct termios options;
     	tcgetattr(xbee_stream, &options);
     	cfsetispeed(&options, B9600);
     	cfsetospeed(&options, B9600);
     	options.c_iflag &= ~ICRNL;
     	options.c_oflag &= ~OCRNL;
     	options.c_cflag |= (CLOCAL | CREAD);
     	options.c_cflag &= ~PARENB;
     	options.c_cflag &= ~CSTOPB;
     	options.c_cflag &= ~CSIZE;
     	options.c_cflag |= CS8;
     	options.c_lflag &= ~ICANON;
     	options.c_cc[VMIN] = 1;
     	options.c_cc[VTIME] = 50;
     	if (tcsetattr(xbee_stream, TCSANOW, &options))
+    	{
     		fprintf(stderr, "Error setting attributes.\n");
     		return -1;
+    	}
     	//lockf(xbee_stream, F_LOCK, 0);
     	xbee_listen_thread =
     		(pthread_t*)malloc(sizeof(pthread_t));
     	if (xbee_listen_thread == NULL)
+    	{
     		fprintf(stderr, "%s: Malloc failed.\n", __FUNCTION__);
     		return -1;
+    	}
     	int ret = pthread_create(xbee_listen_thread, NULL,
     	int ret = pthread_create(xbee_listen_thread, NULL,
     		listen_to_xbee, NULL);
     	if (ret)
+    	{
     		printf("Failed to create listener thread.\r\n");
     		exit(0);
     		fprintf(stderr, "Failed to create listener thread.\r\n");
     		return -1;
+    	}
     	#endif
     	xbee_enter_command_mode();
     	xbee_enter_api_mode();
-...
     	//wait to return until the address is set
     	while (xbee_address == 0) xbee_get_packet(NULL);
     	return 0;
+    }
     /**
-...
     	lockf(xbee_stream, F_ULOCK, 0);
     	close(xbee_stream);
     	#endif
     	queue_destroy(xbee_queue);
+    }
     /**
-...
+    }
     /**
      * Exit API mode. (warning - does not check for response)
      **/
     void xbee_exit_api_mode()
+    {
     	xbee_send_string("ATAP 0\r");
+    }
     /**
      * Wait until the string "OK\r" is received from the XBee.
      **/
     void xbee_wait_for_ok()
-...
     	char* curr = s;
     	while (curr - s < len)
+    	{
     		if (queue_is_empty(xbee_queue))
     		// check if buffer is empty
     		if (buffer_last == buffer_first)
     			continue;
     		char c = (char)(int)queue_remove(xbee_queue);
     		char c = arrival_buf[buffer_first++];
     		if (buffer_first == XBEE_BUFFER_SIZE)
     			buffer_first = 0;
     		if (c == *curr)
     			curr++;
     		else
-...
     	if (currentBufPos == 0)
+    	{
     		do
     			if (queue_is_empty(xbee_queue))
+    		{
     			if (buffer_first == XBEE_BUFFER_SIZE)
     				buffer_first = 0;
     			// check if buffer is empty
     			if (buffer_first == buffer_last)
     				return -1;
     		while ((char)(int)queue_remove(xbee_queue) != XBEE_FRAME_START);
+    		}
     		while (arrival_buf[buffer_first++] != XBEE_FRAME_START);
     		if (buffer_first == XBEE_BUFFER_SIZE)
     			buffer_first = 0;
     		xbee_buf[0] = XBEE_FRAME_START;
     		currentBufPos++;
+    	}
-...
     				return -1;
+    			}
+    		}
     		if (queue_is_empty(xbee_queue))
     		// check if buffer is empty
     		if (buffer_first == buffer_last)
     			return -1;
     		xbee_buf[currentBufPos++] = (char)(int)queue_remove(xbee_queue);
     		xbee_buf[currentBufPos++] = arrival_buf[buffer_first++];
     		if (buffer_first == XBEE_BUFFER_SIZE)
     			buffer_first = 0;
+    	}
     	currentBufPos = 0;
-...
+    }
     #ifndef ROBOT
     void xbee_set_com_port(char* port){
       //printf("Port being passed is %s\n",port);
       xbee_com_port = (char *) malloc(strlen(port));
       strcpy(xbee_com_port,port);
     void xbee_set_com_port(char* port)
+    {
     	xbee_com_port = port;
+    }
     #endif

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Revision 336