blackfox Posted June 22, 2013 Share Posted June 22, 2013 Hello, I'm testing the weather station with PHP. For WeatherStationWebsite.php I use: <?php require_once('Tinkerforge/IPConnection.php'); require_once('Tinkerforge/BrickletAmbientLight.php'); require_once('Tinkerforge/BrickletHumidity.php'); require_once('Tinkerforge/BrickletBarometer.php'); use Tinkerforge\IPConnection; use Tinkerforge\BrickletAmbientLight; use Tinkerforge\BrickletHumidity; use Tinkerforge\BrickletBarometer; $ipcon = new IPConnection(); $brickletAmbientLight = new BrickletAmbientLight("enG", $ipcon); $brickletHumidity = new BrickletHumidity("eFY", $ipcon); $brickletBarometer = new BrickletBarometer("eUy", $ipcon); $ipcon->connect("localhost", 4223); $illuminance = $brickletAmbientLight->getIlluminance()/10.0; $humidity = $brickletHumidity->getHumidity()/10.0; $air_pressure = $brickletBarometer->getAirPressure()/1000.0; $temperature = $brickletBarometer->getChipTemperature()/100.0; $response = array ( "illuminance" => "Illuminance: $illuminance Lux", "humidity" => "Humidity: $humidity %RH", "air_pressure" => "Air Pressure: $air_pressure mbar", "temperature" => "Temperature: $temperature °C", ); print_r(json_encode($response)); ?> But the result is: {"illuminance":"Illuminance: 1.7 Lux","humidity":"Humidity: 68.6 %RH","air_pressure":"Air Pressure: 1001.318 mbar","temperature":null} What is the correct code to retrieve the temperature from the barometer bricklet? Quote Link to comment Share on other sites More sharing options...
JavaLaurence Posted June 23, 2013 Share Posted June 23, 2013 Is the divide by 100 the problem? What does it produce if you don't divide at all? Quote Link to comment Share on other sites More sharing options...
blackfox Posted June 24, 2013 Author Share Posted June 24, 2013 I've changed the number into 10.0, 100.0, 1000.0 and 10000.0, but it all gave the same result, then I've removed the division altogether but the result stays on "null". Quote Link to comment Share on other sites More sharing options...
borg Posted June 24, 2013 Share Posted June 24, 2013 "null" means probably that the object "null" is returned, not the integer 0. Are the PHP Bindings up to date? Quote Link to comment Share on other sites More sharing options...
blackfox Posted June 24, 2013 Author Share Posted June 24, 2013 PHP Version 5.4.4-14+deb7u2 BCMath support enabled include_path .:/usr/share/php:/usr/share/pear Recent download: pear install Tinkerforge.tgz And may I add that WeatherStation.php does work and gives me a correct temperature. But I cannot get a temperature with WeatherStationWebsite.php. Quote Link to comment Share on other sites More sharing options...
borg Posted June 24, 2013 Share Posted June 24, 2013 If you print $temperature, is that also "null"? Your PHP seems to evaluate "Temperature: $temperature °C" as null. I am not sure why that is. Perhaps you can try to change the string bit for bit, to find what excatly the reason is! Quote Link to comment Share on other sites More sharing options...
blackfox Posted June 24, 2013 Author Share Posted June 24, 2013 It seems that the ° in front of the C causes the problem. By omitting the ° I get a response: {"illuminance":"Illuminance: 838.1 Lux","humidity":"Humidity: 61 %RH","air_pressure":"Air Pressure: 1013.163 mbar","temperature":"Temperature: 20.46 C"} Adding a ° gives always a null no mater where it is put. Is ° a not accepted character in PHP? Quote Link to comment Share on other sites More sharing options...
borg Posted June 24, 2013 Share Posted June 24, 2013 That seems to be a string encoding problem. I just tested it on my PC, here the strings seem to be encoded as utf-8. You probably have to enable utf-8 encoding in your php.ini: http://stackoverflow.com/questions/1605760/how-to-best-configure-php-to-handle-a-utf-8-website Quote Link to comment Share on other sites More sharing options...
blackfox Posted June 26, 2013 Author Share Posted June 26, 2013 utf-8 encoding wasn't the problem. I fixed it as follows: Changed: "temperature" => "Temperature: $temperature °C" To: "temperature" => "Temperature: $temperature °C" Or: "temperature" => "Temperature: $temperature °C" So the °C was changed to &decC or to °C This gives the correct response: Temperature: 18.83 °C Quote Link to comment Share on other sites More sharing options...
photron Posted July 3, 2013 Share Posted July 3, 2013 I changed the example to use ° to make it less error prone. Quote Link to comment Share on other sites More sharing options...
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