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.
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.
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"
Settings/Status
Import programXBeeApiSimpleATCmdsExample
Simple example of using XBeeApi to send AT-style commands to the XBee
Import programXBeeApiRemoteATCmdsExample
Example of using the XBeeApi library to send AT commands to remote XBee devices in order to read/write settings
Receive
Import programXBeeApiSimpleReceiveExample
Simple example of using XBeeApi to receive data packets via wireless
Import programXBeeApiReceiveCallbackExample
Example of using the XBeeApi library to receive a message via a callback method
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
Remote I/O
Import programXBeeApiRemoteIOExample
Example of using the XBeeApi library to read inputs on a remote XBee
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.
Revision 49:37bba77ee73f, committed 2014-07-07
- Comitter:
- johnb
- Date:
- Mon Jul 07 19:14:46 2014 +0000
- Parent:
- 48:48397bedf95d
- Child:
- 50:f76b7e7959a2
- Commit message:
- Add sanity check to RX'd message length
Changed in this revision
Base/XBeeDevice.cpp | Show annotated file Show diff for this revision Revisions of this file |
--- a/Base/XBeeDevice.cpp Mon Jul 07 19:03:09 2014 +0000 +++ b/Base/XBeeDevice.cpp Mon Jul 07 19:14:46 2014 +0000 @@ -18,10 +18,11 @@ #include "XBeeDevice.hpp" #include "XBeeApiCfg.hpp" +#include "XBeeApiTxFrame.hpp" /** Number of bytes we need to 'peek' into the receive buffer in order to retrieve the payload length */ -#define INITIAL_PEEK_LEN (3U) +#define INITIAL_PEEK_LEN XBEE_API_FRAME_OVERHEAD_START /** Enum of bytes with a special meaning when communicating with the XBee in API mode. In escaped mode, these are the bytes that need to be escaped */ @@ -209,46 +210,53 @@ { /* 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 ) + + /* Safety check */ + if( cmdLen <= ( XBEE_API_MAX_TX_PAYLOAD_LEN + XBEE_API_FRAME_OVERHEAD )) { - bool doProcess = true; - - /* Checksum verification, performed only if it's configured */ - if( !m_ignoreBadCsum ) + uint8_t cmdBuff[cmdLen]; + /* TODO: could consider not "peek" ing here, but working on the rxBuff directly! Would save (stack) memory at + the expense of a little speed, but would need decoder API to change (decodeCallback()) ... */ + uint16_t len = m_rxBuff.peek( cmdBuff, cmdLen ); + + /* Check that we've received the entire frame */ + if( len >= cmdLen ) { - if( !verifyFrameChecksum( cmdBuff, cmdLen )) + bool doProcess = true; + + /* Checksum verification, performed only if it's configured */ + if( !m_ignoreBadCsum ) { - doProcess = false; - m_badCsumCount++; - } - } - - if( doProcess ) - { - /* 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 ) + if( !verifyFrameChecksum( cmdBuff, cmdLen )) { - break; + doProcess = false; + m_badCsumCount++; } } - } - /* 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; + + if( doProcess ) + { + /* 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 ); + + /* Successfully decoded 1 message ... there may be more waiting in the buffer! */ + cont = true; + } } } } while( cont );