phpXBee.php

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<?php
require 'BayEOSSerialPHP.php';
define("XBEE_ESCAPE",pack("C",0x7d));
define("XBEE_DELIM",pack("C",0x7e));
define("XON",pack("C",0x11));
define("XOFF",pack("C",0x13));
class XBee extends phpSerial {
        private $stack;
        function XBee() {
                $this->stack=array();
                parent::phpSerial();
        }

        public function confDefaults($device = '/dev/ttyUSB0') {
                $this -> deviceSet($device);
                $this -> confBaudRate(38400);
                $this -> confParity('none');
                $this -> confCharacterLength(8);
                $this -> confStopBits(1);
                $this -> confFlowControl('none');
        }
        
        public function open($waitForOpened=0.1) {
                $this -> deviceOpen();
                  usleep((int) ($waitForOpened * 1000000));
        }

        public function close() {
                $this -> deviceClose();
        }
        
        public function send($frame , $waitForReply=0) {
                $frame=XBEE_DELIM.$this->_escape($frame);
                $this -> sendMessage($frame, $waitForReply);                
                //echo 'Send: '.array_pop(unpack('H*',$frame))."\n";        //debug
        }

        public function read($count = 0){
            $data = $this -> readPort($count);
            //echo 'READ: '.array_pop(unpack('H*',$data))."\n";
            if(! $data) return count($this->stack);
            if(! isset($this->stack[0])){
                $delim_pos=strpos($data,XBEE_DELIM);
                if($delim_pos===FALSE) return 0;
                else $data=substr($data,$delim_pos+1);
            }
            
            $data=explode(XBEE_DELIM,$data);
            $offset=count($this->stack)-1;
            if($offset==-1) $offset=0;
            for($i=0;$i<count($data);$i++){
                $index=$i+$offset;
                if(! isset($this->stack[$index]['ts']))
                    $this->stack[$index]['ts']=microtime(TRUE);
                if(! isset($this->stack[$index]['rawframe'])) 
                    $this->stack[$index]['rawframe']='';
                $this->stack[$index]['rawframe'].=$data[$i];
                $this->stack[$index]['frame']=$this->_unescape($this->stack[$index]['rawframe']);
                $this->stack[$index]['ok']=$this->_parseFrame($this->stack[$index]['frame']);
                if(! $this->stack[$index]['ok'] && ($i+1)<count($data)){
                    //Invalid Frame!
                    unset($this->stack[$index]);
                    $offset--; 
                    fwrite(STDERR,date('Y-m-d H:i:s').' '.$this->_device." : Invalid frame\n");
                }
            }
            
            $anz=count($this->stack);
            //echo "Stackcount: $anz\n";
            if(! $this->stack[$anz-1]['ok']) $anz--;
            return $anz;
        }
        
        public function getPANID(){
            $this->send(pack('C7',0x00,0x04,0x08,0x01,0x49,0x44,0x69));
            
            while(($data=$this->getFrame())){
                $f=$data['frame'];
                //echo "Got:".array_pop(unpack('H*',$f))."\n";
                if($f[2]==pack("C",0x88) && $f[4]=='I' && $f[5]=='D' && $f[6]==pack("C",0x0)){
                    return array_pop(unpack('n',substr($f,7,2)));
                }       
            }
            die("Could not get PANID\n");
        }
        
        private function _parseFrame($frame){
            if(strlen($frame)<3) return FALSE;
            $length = substr($frame, 0, 2);
            $checksum = substr($frame, -1);
            $cmdData = substr($frame, 2, -1);
            $calculatedChecksum = $this -> _calcChecksum($cmdData);
            $calculatedLength = pack('n',strlen($cmdData));
            
            //echo "parseFrame: ".array_pop(unpack('H*',$frame.$calculatedChecksum.$checksum.$calculatedLength.$length))."\n";
            if ($checksum === $calculatedChecksum && $length === $calculatedLength) {
                return TRUE;
            } else {
                return FALSE;
            }
             
        }
        
        
        
        protected function _calcChecksum($data) {
            $checksum = 0;
            for ($i = 0; $i < strlen($data); $i++) {
                $checksum += ord($data[$i]);
            }
            $checksum = $checksum & 0xFF;
            $checksum = 0xFF - $checksum;
            $checksum = chr($checksum);
            return $checksum;
        }
        
        
        public function getFrame($timeout=120){
            while($this->read()==0 && $timeout>0){
                $timeout-=0.01;
                usleep(10000);
            }
            if($timeout<0) return FALSE;
            return array_shift($this->stack);
        }
        
        private function _escape($rawData){
            $res='';
            for($i=0;$i<strlen($rawData);$i++){
                if(in_array($rawData[$i],array(XBEE_ESCAPE,XBEE_DELIM,XOFF,XOFF)))
                    $res.=XBEE_ESCAPE.(pack("C",0x20) ^ $rawData[$i]);  
                else $res.=$rawData[$i];
            }
            return $res;                        
        }
        
        private function _unescape($rawData){
            //echo "Unescape: ".array_pop(unpack('H*',$rawData))."\n";
            $res='';
            for($i=0;$i<strlen($rawData);$i++){
                if($rawData[$i]===XBEE_ESCAPE){
                    //echo "got escape!!\n";
                    $i++;
                    if($i<strlen($rawData))
                        $res.=pack("C",0x20) ^ $rawData[$i];
                } else $res.=$rawData[$i];
            }
            //echo "Unescape: ".array_pop(unpack('H*',$res))."\n";
            return $res;
        }
                
}

?>