<?php

# Pollin-NET-IO Ansteuerungs-Klasse
# http://www.pollin.de/shop/dt/MTQ5OTgxOTk-/Bausaetze_Module/Bausaetze/Bausatz_AVR_NET_IO.html

/*
 Pollin NET I/O Control Classs
 Controls the pollin AVR NET I/O board over network.

 Latest version: http://blog.coldtobi.de/1_coldtobis_blog/archive/298_pollin_net-io_php_library.html

 Copyright (C) 2011  Tobias Frost ("coldtobi")

 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 as published by the Free Software Foundation; either version 2
 of the License, or (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

/* Pollin I/O Klasse
 *
 * Supports:
 * - Connect und Disconnect
 * - Query ports (input and output)
 * - Setting the digital output ports
 * - read analog values from the ADC
 *
 * possilble enhancements: (TODO)
 * - LCD Support
 * - Configure network of the board (IP, Netmask, GW)
 * - Read out version info
 * */

class pollin_netio {

	// IP des guten Stückes
	protected $ip_adr;
	// Port -- normalweise 50290.
	protected $port;

	protected $timeout;

	protected $connection;

	// gecachte Statusinfos der Ausgangsports (0..7) und den Eingängen (8..11).
	// array mit 8 Einträgen, "u"=unknown, "1"=high, "0"=low
	protected $portstatus;

	// Construct the object. 
	// ip = IP Address of the Net-IO
	// p = ethernet port, default is the one of the  original firmware (50290)
	// to = network timeout. Default value is 10
	function __construct($ip, $p=50290, $to=10) {
		$this->ip_adr = $ip;
		$this->port = $p;
		$this->timeout = $to;
		$this->connection = false;
	}

	function __destruct() {
		if ($this->connection != false) fclose($this->connection);
	}

	// Connect to the Board. 
	// returns false on error, true on success
	// note: This call is not necessary. The library will automatically
	// whenever it needs to connect. 
	function connect() {
		if ($this->connection != false) return;

		$this->connection =
		fsockopen($this->ip_adr,$this->port,$errno,$errstr,$this->timeout);

		for ($i=0; $i<12 ; $i++) {
			$this->portstatus[$i] = 'u';
		}

		if ( $this -> connection == false) return false;
		return true;
	}

	// Tear down the connection. 
	function disconnect() {
		if ($this->connection != false) fclose($this->connection);
		$this->connection = false;
	}

	// Check IO
	// if cacheok is true, it is ok to returned cached values (that is if 
	// an ouput has been set previously without asking over the network again. Inputs
	// will always be queried.
	// portid specified which port to be read. 0..7 are the output ports 8..11 the inputs
	// ports.  
	function queryio($portid, $cacheok) {

		if ($portid < 0 || $portid >= 12 ) return false;

		if ( $this->connection == false) $this->connect();
		if ( $this->connection == false) return false;

		if ( $cacheok == true && $portid < 8 && $this->portstatus[$portid] != 'u') {
			return $this->portstatus[$portid];
		}

		if ( $portid < 8) {
			$command = "GETSTATUS\r\n";
			if (fwrite($this->connection, $command) == false) return false;
			$answer = fgets($this->connection);
			if ( $answer == false) return false;
			// Anwort ist "Sxxxxxxxx"
			// für x=0 für low, 1 für high
			// Portsnummern: S87654321
			$answer = trim($answer); // Whitespaces weg (CR, LF am Ende)
			if (strlen($answer) != 9) return false; // nicht erwartete Anwort
			$start  = substr($answer,0,1);
			$answer = substr($answer,1);
			if ( $start != 'S') return false;

			$i=0;
			foreach (str_split($answer) as $chr) {
				$this->portstatus[$i++] = $chr;
			}
			return $this->portstatus[$portid];
		}
		// Eingänge, die muss man immer abfragen....
		$realport = $portid - 7;
		$command = "GETPORT ".$realport. "\r\n";
		if (fwrite($this->connection, $command) == false) return false;
		$answer = fgets($this->connection);
		if ( $answer == false) return false;
		$answer = trim($answer); // Whitespaces weg (CR, LF am Ende)
		if ( $answer == '0') {
			$this->portstatus[$portid] = 0;
			return 0;
		} elseif ( $answer == '1') {
			$this->portstatus[$portid] = 1;
			return 1;
		} else {
			return false;
		}
	}

	// Set the output port to a specified value
	// portid = port to be set
	// value = 0 for low, 1 for high	
	function setport($portid, $value) {
		if ( $portid >= 8 ) return false;
		
		if ( $this->connection == false) $this->connect();
		if ( $this->connection == false) return false;
		
		$command = "SETPORT " . ($portid+1) . "." .$value . "\r\n";
		if (fwrite($this->connection, $command) == false) return false;
		$answer = fgets($this->connection);
		if ( $answer == false) return false;
		
		if ( trim($answer) == "ACK") { 
			$this->portstatus[$portid] = $value;
			return true;
		}
		
		$this->portstatus[$portid] = 'u';
		return false;
	}

	// Read the ADC value from the analog inputs. (0...1023) 
	// returns the value on success, false on error. 
	function queryad($portid) {
		if ($portid > 4) return false;
		
		if ( $this->connection == false) $this->connect();
		if ( $this->connection == false) return false;
		
		$command = "GETADC ". ($portid+1) . "\r\n";
		if (fwrite($this->connection, $command) == false) return false;
		$answer = fgets($this->connection);
		if ( $answer == false) return false;
		$answer = trim($answer);
		if ( !is_numeric($answer)) return false;
		return (int)$answer;
	}

	// Not yet implemented!
	function writedisplay($string, $line) {
		return false; 
	}

	// Not yet implemented!
	function cleardisplay() {
		return false; 
	}
	
}

 
?>