WebClient and MotionDetector stops after a while - c++

Question

I've been digging this for around a week and doesn't have any way to solve this one. My Arduino code is working for a while (few times / few days) and then stops all of a sudden. I'm trying to implement a WebClient within the Arduino which sends HTTP GET requests to some other server every time (periodically - every 90 seconds) when a motion had been detected / when motion had stopped.
Below you can find the code. Can anyone assist?
#include <Ethernet2.h>
#include <SPI.h>
byte mac[] = { 0x90, 0xA2, 0xDA, 0x10, 0x73, 0x88 };
IPAddress ip(192,168,20,84);
IPAddress server(192,168,50,93); // Google
IPAddress myDns(8, 8, 8, 8);
EthernetClient client;
//getMovement - sends a GET request when motion is detected
void getMovement() {
client.stop();
if (client.connect(server, 8080)) {
client.println("GET /GetARoomMaven/motion?roomId=1&movement=1");
client.println();
Serial.println("Movement Request Sent");
} else {
Serial.println("connection failed");
}
}
//getNoMovement - sends a GET request when motion had stopped
void getNoMovement() {
client.stop();
if (client.connect(server, 8080)) {
client.println("GET /GetARoomMaven/motion?roomId=1&movement=0");
client.println();
Serial.println("Movement Request Sent");
} else {
Serial.println("connection failed");
}
}
//VARS
//the time we give the sensor to calibrate (10-60 secs according to the datasheet)
int calibrationTime = 10;
//the time when the sensor outputs a low impulse
long unsigned int lowIn;
//the amount of milliseconds the sensor has to be low
//before we assume all motion has stopped
long unsigned int pause = 90000;
//
boolean lockLow = true;
boolean takeLowTime;
int pirPin = 2; //the digital pin connected to the PIR sensor's output
int ledPin = 13;
/////////////////////////////
//SETUP
void setup(){
Serial.begin(9600);
pinMode(pirPin, INPUT);
pinMode(ledPin, OUTPUT);
digitalWrite(pirPin, LOW);
Ethernet.begin(mac);
//give the sensor some time to calibrate
Serial.print("calibrating sensor ");
for(int i = 0; i < calibrationTime; i++){
Serial.print(".");
delay(1000);
}
Serial.println(" done");
Serial.println("SENSOR ACTIVE");
delay(50);
loop();
}
////////////////////////////
//LOOP
void loop(){
if(digitalRead(pirPin) == HIGH){
digitalWrite(ledPin, HIGH); //the led visualizes the sensors output pin state
if(lockLow){
//makes sure we wait for a transition to LOW before any further output is made:
lockLow = false;
Serial.print("motion detected at ");
Serial.print(millis()/1000);
Serial.println(" sec");
getMovement();
}
takeLowTime = true;
}
if(digitalRead(pirPin) == LOW){
digitalWrite(ledPin, LOW); //the led visualizes the sensors output pin state
if(takeLowTime){
lowIn = millis(); //save the time of the transition from high to LOW
takeLowTime = false; //make sure this is only done at the start of a LOW phase
}
//if the sensor is low for more than the given pause,
//we assume that no more motion is going to happen
if(!lockLow && millis() - lowIn > pause){
//makes sure this block of code is only executed again after
//a new motion sequence has been detected
lockLow = true;
Serial.print("motion ended at "); //output
Serial.print((millis() - pause)/1000);
Serial.println(" sec");
getNoMovement();
}
}
}

Answer 1

It's hard to say without a better description of symptoms.
Are the LED still blinking ?
If yes, the socket code seems wrong to me:
void getMovement() {
client.stop();
You must remember that TCP requires connection tracking, so you can't immediately stop a socket, it has to linger a bit for acknowledging packets sent.
If you look at the implementation:
void EthernetClient::stop() {
if (_sock == MAX_SOCK_NUM)
return;
[...]
}
stop() will fail if you have more than MAX_SOCK_NUM (which is 4 on your platform) opened at a time. Can this happen?
In all case, you should avoid as much as possible dynamic allocations, you should have a single function sendMovement(bool detected) that's writing the detected value (getMovement and getNoMovement are the same function, so factorize them). You should re-use the client as much as possible (avoid closing the socket and re-opening it unless you get an error from any socket function). Finally, you might want to set up an interrupt on the digital input pin (with some software debouncing) to avoid polling on it, that would release CPU, and, depending on the configuration, might release more time to process SPI messages.
If the LED are not blinking, try to comment out the SPI related code (EthernetClient's code) and check if it works (in that case, I would check the HW for errors, some of the socket code is busy looping (socket::send does this) that would never finish and stop your loop function from progressing. In that case, if you use JTAG to pause the CPU, it'll be in the client.connect or client.println method.
If it still does not work (LED not blinking with no SPI code), then the issue is likely hardware, check voltage / temperature / JTAG connect to the board to interrupt the CPU to figure out where it's struck.
BTW, if you are doing HTTP, the request is wrong and should be:
GET url HTTP/1.1\r\n
Host: yourserverhost.com\r\n
Connection: Keep-Alive\r\n
\r\n
The part HTTP/1.x after the GET url is absolutely required even for HTTP/1.0. Unless you've written your own server (in that case, there's no need to mimick HTTP), it should not work at all, not even once.