John Bailey / XBeeApi

API for communicating with XBee devices.

Dependencies:   CircularBuffer FixedLengthList

Dependents:   XBeeApiTest XBeeApiSimpleATCmdsExample XBeeApiBroadcastExample XBeeApiBroadcastExampleRTOS ... more

Overview

XBeeApi is intended to be a library for providing a high-level API interface to the XBee - for example getChannel() and setChannel(2) methods rather than needing to send( "ATCH" ) and send( "ATCH 2" ) - and then de-code the responses.

See the notebook page here for a description of how the API works & some details on the various classes.

Features:

  • Support for transmission & reception of data packets
  • Support for reading & changing settings
  • Support for "Remote AT" interface to access settings & I/O channels on remote XBees
  • XBeeApi should work if you're using mbed-rtos, though it is not currently threadsafe. Take a look at the XBeeApiBroadcastExampleRTOS example if you're including mbed-rtos.

Example Programs

There are also example programs available:

Transmit

Import programXBeeApiSimpleBroadcastExample

Simple example of how to use XBeeApi - set up the XBee, configure P2P networking then transmit a frame.

Last commit 06 Jul 2014 by John Bailey

Import programXBeeApiBroadcastExample

Example for XBeeAPI; a little more involved than XBeeApiSimpleBroadcastExample with report on failure to set up the XBee and on the transmit status of the message.

Last commit 05 Jul 2014 by John Bailey

Import programXBeeApiBroadcastExampleRTOS

Example of using the XBeeApi library to broadcast a message, based on XBeeApiBroadcastExample. This example shows how to use the library when using mbed-rtos. Before compiling you must open "XbeeApi\Config\XBeeApiCfg.hpp" and change the '#if 0' to '#if 1' on the line above the comment reading "Use RTOS features to make XBeeApi threadsafe"

Last commit 06 Jul 2014 by John Bailey

Settings/Status

Import programXBeeApiSimpleATCmdsExample

Simple example of using XBeeApi to send AT-style commands to the XBee

Last commit 31 Mar 2014 by John Bailey

Import programXBeeApiRemoteATCmdsExample

Example of using the XBeeApi library to send AT commands to remote XBee devices in order to read/write settings

Last commit 13 Jul 2014 by John Bailey

Receive

Import programXBeeApiSimpleReceiveExample

Simple example of using XBeeApi to receive data packets via wireless

Last commit 08 Jul 2014 by John Bailey

Import programXBeeApiReceiveCallbackExample

Example of using the XBeeApi library to receive a message via a callback method

Last commit 08 Jul 2014 by John Bailey

Import programXBeeApiReceiveCallbackExampleRTOS

Example of using the XBeeApi library to receive a message via a callback method. This example shows how to use the library when using mbed-rtos. See the comment at the top of main.cpp

Last commit 08 Jul 2014 by John Bailey

Remote I/O

Import programXBeeApiRemoteIOExample

Example of using the XBeeApi library to read inputs on a remote XBee

Last commit 28 Jul 2014 by John Bailey

If you have 2 mbed connected XBees available then you can use XBeeApiSimpleReceiveExample and XBeeApiSimpleBroadcastExample as a pair.

Note that this is still a work in progress! XBeeApiTodoList tracks some of the functionality still to be added.

Diff: Base/XBeeDevice.cpp

Revision:
7:2f1e157cdd1c
Parent:
6:3cb62daace78
Child:
8:1b48b619d7f6
--- a/Base/XBeeDevice.cpp	Wed Jan 29 20:33:17 2014 +0000
+++ b/Base/XBeeDevice.cpp	Thu Jan 30 21:28:57 2014 +0000
@@ -99,48 +99,70 @@
     
     if( m_inAtCmdMode ) 
     {
+        /* Safeguard - if we're in cmd mode, clear out status associated with API mode */
         m_rxMsgLastWasEsc = false;
     } 
- 
-    checkRxDecode();
+    else 
+    {
+        /* Check to see if there's API data to decode */
+        checkRxDecode();
+    }
 }
     
+extern Serial pc;
+    
 void XBeeDevice::checkRxDecode( void )
 {
-    /* Get an initial portion of data from the read buffer so that the message length can be determined */
     uint8_t buff[INITIAL_PEEK_LEN];
-    uint16_t len = m_rxBuff.peek( buff, INITIAL_PEEK_LEN );    
+    bool cont = false;
     
-    if((len >= INITIAL_PEEK_LEN ) &&
-       (buff[ XBEE_CMD_POSN_SDELIM ] == XBEE_SB_FRAME_DELIMITER ))
+    /* Ensure that we're delimiter aligned - this should allow recovery in the case that
+       we've missed bytes and somehow become unaligned */
+    while( m_rxBuff.getSize() &&
+          ( m_rxBuff[0] != XBEE_SB_FRAME_DELIMITER ))
     {
-        /* Try and get enough data to cover the whole message */
-        /* TODO: Magic number */
-        const uint16_t cmdLen = MSG_LEN_IN_BUFFER( buff ) + XBEE_API_FRAME_OVERHEAD;
-        uint8_t cmdBuff[cmdLen];
-        uint16_t len = m_rxBuff.peek( cmdBuff, cmdLen );    
-
-        if( len >= cmdLen )
+        m_rxBuff.chomp( 1 );
+    }
+    
+    do {
+        /* Get an initial portion of data from the read buffer so that the message length can be determined */
+        uint16_t len = m_rxBuff.peek( buff, INITIAL_PEEK_LEN );    
+        cont = false;
+        
+        /* Ensure that sufficient data was received - already know that we should be delimiter aligned based on the above */
+        if( len >= INITIAL_PEEK_LEN ) 
         {
-            /* TODO: Verify checksum */
-            
-            /* Iterate all of the decoders */
-            for( FixedLengthList<XBeeApiFrameDecoder*, XBEEAPI_CONFIG_DECODER_LIST_SIZE>::iterator it = m_decoders.begin() ;
-                 it != m_decoders.end();
-                 ++it ) {
+            /* Try and get enough data to cover the whole message */
+            const uint16_t cmdLen = MSG_LEN_IN_BUFFER( buff ) + XBEE_API_FRAME_OVERHEAD;
+            uint8_t cmdBuff[cmdLen];
+            uint16_t len = m_rxBuff.peek( cmdBuff, cmdLen );    
+    
+            /* Check that we've received the entire frame */
+            if( len >= cmdLen )
+            {
+                /* TODO: Verify checksum */
+                
+                /* Iterate all of the decoders */
+                for( FixedLengthList<XBeeApiFrameDecoder*, XBEEAPI_CONFIG_DECODER_LIST_SIZE>::iterator it = m_decoders.begin() ;
+                     it != m_decoders.end();
+                     ++it ) {
+    
+                    bool processed = (*it)->decodeCallback( cmdBuff, cmdLen );
+                    if( processed )
+                    {
+                        break;
+                    }
+                }            
+                /* Remove the data from the receive buffer - either it was decoded (all well and good)
+                   or it wasn't, in which case we need to get rid of it to prevent it from jamming
+                   up the message queue */
+                m_rxBuff.chomp( cmdLen );
 
-                bool processed = (*it)->decodeCallback( cmdBuff, cmdLen );
-                if( processed )
-                {
-                    break;
-                }
-            }            
-            /* Remove the data from the receive buffer - either it was decoded (all well and good)
-               or it wasn't, in which case we need to get rid of it to prevent it from jamming
-               up the message queue */
-            m_rxBuff.chomp( cmdLen );
+                /* Successfully decoded 1 message ... there may be more waiting in the buffer! */                
+                cont = true;
+            }
         }
-    }
+    } while( cont );
 }
 
 bool XBeeDevice::registerDecoder( XBeeApiFrameDecoder* const p_decoder )
@@ -148,7 +170,9 @@
     bool ret_val = false;
     if( p_decoder != NULL )
     {
-        if( !m_decoders.inList( p_decoder ) ) {
+        /* Check if decoder already registered */
+        if( !m_decoders.inList( p_decoder ) ) 
+        {
             m_decoders.push( p_decoder );   
             p_decoder->registerCallback( this );
             ret_val = true;
@@ -162,15 +186,10 @@
     bool ret_val = false;
     if( p_decoder != NULL )
     {
-        /* Iterate all of the decoders */
-        for( FixedLengthList<XBeeApiFrameDecoder*, XBEEAPI_CONFIG_DECODER_LIST_SIZE>::iterator it = m_decoders.begin() ;
-             it != m_decoders.end();
-             ++it ) {
-            if( *it == p_decoder ) {
-                p_decoder->unregisterCallback();
-                /* TODO: Actually remove the item from m_decoders! */
-                ret_val = true;   
-            }
+        if( m_decoders.remove( p_decoder ) )
+        {
+            p_decoder->unregisterCallback();
+            ret_val = true;   
         }
     }
     return ret_val;