I'm a beginner currently working on a project using a raspberrypi3 with a LAMP stack, and an arduino with some sensors for recording telemetry.
I'm stuck right now, as my Python script to import data into MySQL can connect to /dev/ttyACM0 when triggered within the shell, and works perfectly. When triggered system(), popen(), or exec() in PHP it fails to connect to the serial port.
I know that the script is running because in the PHP output, it shows the message with failed to connect to /dev/ttyAMC0
This is my first time ever using PHP, so it might be something really dumb.
Currently I've referenced these sites for my current problem:
Calling Python in PHP
Execute PHP function with onClick
PHP - Command Line
Here is the code from my index.php:
@charset "utf-8";
body {
background-color: rgba(233,233,233,1.00);
font-family: Gotham, "Helvetica Neue", Helvetica, Arial, sans-serif;
font-size: x-large;
}
h1 {
color: rgba(233,233,233,1.00);
background-color: rgba(55,55,55,1.00);
padding-top: 5px;
padding-right: 5px;
padding-bottom: 5px;
padding-left: 5px;
}
.button {
display: inline-block;
padding-top: 30px;
padding-right: 30px;
padding-bottom: 30px;
padding-left: 30px;
background-color: rgba(55,55,55,1.00);
color: rgba(233,233,233,1.00);
text-align: center;
margin-top: 10px;
margin-right: 10px;
margin-bottom: 10px;
margin-left: 10px;
}<!doctype html>
<?php
function start_recording(){
system("./getdata.py");
}
function stop_recording(){
popen("pkill python");
}
if (isset($_GET['start'])) {
start_recording();
}
if (isset($_GET['stop'])) {
stop_recording();
}
?>
<html>
<head>
<meta charset="utf-8">
<title>Telemetry Computer</title>
<link href="/assets/stylesheet.css" rel="stylesheet" type="text/css">
</head>
<body>
<h1>Telemetry Box OS v1.0.0</h1>
<h4>by Jake Johnson</h4>
<a href="?start=true">
<div class="button">Start Recording Data</div>
</a><br>
<a href="?stop=true">
<div class="button">Kill Recording</div>
</a><br>
<a href="/data">
<div class="button">View Data</div>
</a><br>
<a href="/manage">
<div class="button">Data Managment</div>
</a>
</body>
</html>
and here is my python:
#!/usr/bin/python
import serial
import MySQLdb
#establish connection to MySQL. You'll have to change this for your database.
dbConn = MySQLdb.connect(host="localhost", user="ayylmao", passwd="ayylmao", db="telemetry") or die ("could not connect to database")
#open a cursor to the database
device = '/dev/ttyACM0'
try:
print "Trying...",device
arduino = serial.Serial(device, 9600)
except:
print "Failed to connect on",device
while True:
cursor = dbConn.cursor()
try:
print("--------- Inserting Data ---------")
data = arduino.readline() #read the data from the arduino
pieces = data.split("\t") #split the data by the tab
#insert the data into the Database
try:
cursor.execute("INSERT INTO telemetryData (runTime,tempF,rpm,xforce,yforce,zforce) VALUES (%s,%s,%s,%s,%s,%s)", (pieces[0],pieces[1],pieces[2],pieces[3],pieces[4],pieces[5]))
dbConn.commit() #commit the insert
cursor.close() #close the cursor
except MySQLdb.IntegrityError:
print "failed to insert data"
finally:
cursor.close() #close just incase it failed
except:
print "Failed to get data from Arduino!"
