Can't connect to Xively using Arduino + wifi shield, "ret = -1 No sockets available"

Question

Thanks so much for looking guys. I'm just getting started with Arduino wireless sensor projects and I've hit a clue wall. I'd appreciate any insight or help troubleshooting my project.

I'm using an Arduino Mega, with the Wifi Shield to attempt to upload 4 channels (all floats) to my Xively feed. I'm using a modified form of the basic tutorial script (code at bottom). I verify and upload successfully. When I run the board, the initial debugging info looks good. When I attempt to do either a put or a get using the Xively client library I get an error (ret = -1, no sockets available, and http error on gets). I've attached a serial log of the errors at the bottom as well.

I've taken some troubleshooting steps already. I've re-downloaded all the xively libraries, and Wifi libraries to be sure. I thought manually setting a DNS server (8.8.8.8) might help. I even imported the whole arduino library (although I don't think it should be needed) to get the DNS functionality. It did not seem to make a difference, so I left it in as a troubleshooting breadcrumb. Also as a troubleshooting step, I added a Xively client.get to see if I could pull but not push. That generated an HTTP error. I also added a public wide open api key to my project and tried that (instead of the private one). Still no joy.

It sorta feels like although I'm connecting successfully to my wifi, but can't make a real connection to any services. I was hoping there was some super obvious step I missed. I could really use a helpful clue to get me on the right track again. thanks!

Micah Wyenn

#include <Dhcp.h>
#include <Dns.h>
#include <Ethernet.h>
#include <EthernetClient.h>
#include <EthernetServer.h>
#include <EthernetUdp.h>
#include <util.h>

/*
     Hot Tub Monitor 
         --- If you are only calibrating your sensor, use the calibrate sensor script.  This is for submerged operation.
     This script will allow you to test to ensure the temp, Ph, and ORD sensors are operating and are calibrated correctly.----

     This script was written for the MEGA 2560 with the wireless shield, connecting in to Xively's cloud graph service

     The Mega 2560 with the Wireless shield and Probes uses the following pins:
     *  SPI bus interface 
     *  Onboard MicroSD card reader (uses SD Lib) on digital pin 4
     *  Digital Pins 7, 50, 51, 52, and 53 are reserved and shouldn't be used
     *  Digital Pin 18 is set to OUTPUT to power the temp probe on/off 
     *  Atlas Scientific Temp Sensor input on Analog Uno pin A4
     *  Phidgets Ph Sensor input on Analog Uno pin A2
     *  Phidgets ORD Sensor input on Analog Uno pin A0
*/
// Libraries in use
#include <SPI.h>
#include <WiFi.h>
#include <b64.h>
#include <HttpClient.h>
#include <CountingStream.h>
#include <Xively.h>
#include <XivelyClient.h>
#include <XivelyDatastream.h>
#include <XivelyFeed.h>
#include <WiFiClient.h>
#include <WiFiServer.h>
#include <WiFiUdp.h>

// setting up some of the globals
const int TEMPPIN = 4;
const int PHPIN = 1;
const int ORPPIN = 0;
boolean isDebugEnabled = true;   //setting up the debug state
int status = WL_IDLE_STATUS;
char ssid[] = "<security snip>"; //  your network SSID (name) 
char pass[] = "<security snip>";    // your network password (use for WPA, or use as key for WEP)

// My Xively key to let you upload data
char xivelyKey[] = "<security snip>";
// My xively feed ID
#define xivelyFeed <security snip>
// My datastreams
char myWirelessStrStream[] = "MonitorWirelessStrength";
char myORPStream[] = "ORP";
char myPhStream[] = "Ph";
char myTempStream[] = "Temp";

// Creating the datastreams
XivelyDatastream datastreams[] = {
    XivelyDatastream(myWirelessStrStream, strlen(myWirelessStrStream), DATASTREAM_FLOAT),
    XivelyDatastream(myORPStream, strlen(myORPStream), DATASTREAM_FLOAT),
    XivelyDatastream(myPhStream, strlen(myPhStream), DATASTREAM_FLOAT), 
    XivelyDatastream(myTempStream, strlen(myTempStream), DATASTREAM_FLOAT)
    };
XivelyFeed feed(xivelyFeed, datastreams, 4);

//starting the Xively client
WiFiClient client;
XivelyClient xivelyclient(client);


void setup() {
  if (isDebugEnabled) {   //setting up the debug stream
    Serial.begin(9600);
    Serial.println("Hot Tub Monitor Debug Stream Starting");
    Serial.println("-----------------------------------");
  }
  pinMode(12,OUTPUT);   //this pin turns on the temp sensor - battery saver to have this on/off switchable

  // connect to the wifi
  // check for presence of the shield
  if (WiFi.status() == WL_NO_SHIELD) {
    Serial.println("WiFi shield not present"); 
    // don't continue:
    while(true);
  } 

  //Connect to the wifi network
    while ( status != WL_CONNECTED) { 
      Serial.print("Attempting to connect to WPA SSID: ");
      Serial.println(ssid);
      // Connect to WPA/WPA2 network:    
      status = WiFi.begin(ssid, pass);

      // wait 10 seconds for connection:
      delay(10000);
  }
  Serial.println("You're connected to the network");
  Serial.println(status);
  //printCurrentNet();
  printWifiData();

  // print the received signal strength:
  long rssi = WiFi.RSSI();
  Serial.print("signal strength (RSSI):");
  Serial.println(rssi);

}

void loop() {
// report on the WiFi Signal strength  
   long rssi = WiFi.RSSI();
  if (isDebugEnabled) {   //send the signal str to Xively
    Serial.print("Sending RSSI to Xively:  ");
    Serial.println(rssi);
  }
    // print the received signal strength:
  datastreams[0].setFloat(rssi);

//  get the temp from our Atlas Sci probe
  float tempC=get_temp();
  float tempF = (tempC*1.8)+32;
  datastreams[1].setFloat(tempF);

// debugging info for temp
  if (isDebugEnabled) {   //send the temp to Xively
    Serial.print("Sending Temp to Xively:  ");
    Serial.println(tempF);
  }

// get the Ph from our phidget's monitor  
  float Ph=get_Ph(tempC);
  datastreams[2].setFloat(Ph);

// debugging info for Ph
  if (isDebugEnabled) {   //send the Ph to Xively
    Serial.print("Sending Ph to Xively:  ");
    Serial.println(Ph);
  } 

// get the Ph from our phidget's monitor  
  float ORP=get_ORP();
  datastreams[3].setFloat(ORP);

// debugging info for Ph
  if (isDebugEnabled) {   //send the Ph to Xively
    Serial.print("Sending ORP to Xively:  ");
    Serial.println(ORP);
  } 


  Serial.println("Uploading it to Xively");
  int ret = xivelyclient.put(feed, xivelyKey);
  Serial.print("xivelyclient.put returned ");
  Serial.println(ret);


   delay(10000);
}  
float get_Ph(float tempC) {  
  float Ph = analogRead(PHPIN);
  Ph = 7 -((2.5 - (Ph/200))/((0.257179 + 0.0000941468)*tempC));  // convert to the ph
  return Ph;
  }

float get_ORP() {
  float ORP = analogRead(ORPPIN);
  ORP = (2.5 - (ORP/200))/1.037;  // convert to proper ORP
  return ORP;
  } 

 float get_temp(){      
  float v_out;
  float Temp;
  digitalWrite(A4, LOW);   //wtf is this for?
  digitalWrite(12, HIGH);
  delay(2);
  v_out = analogRead(4);
  digitalWrite(12, LOW);
  v_out*=.0048;
  v_out*=1000;
  Temp=0.0512 * v_out -20.5128;
  return Temp;
}

void printWifiData() {
  // print your WiFi shield's IP address:
  IPAddress ip = WiFi.localIP();
  Serial.print("IP Address: ");
  Serial.println(ip);
  Serial.println(ip);
}

 
    -----------------------------Error Log Output------------------------------------------
    Hot Tub Monitor Debug Stream Starting
    -----------------------------------
    Attempting to connect to WPA SSID: LionsGate
    You're connected to the network
    3
    IP Address: 192.168.1.137
    192.168.1.137
    signal strength (RSSI):-27
    Sending RSSI to Xively:  -27
    Sending Temp to Xively:  227.32
    Sending Ph to Xively:  6.98
    Sending ORP to Xively:  0.49
    Uploading it to Xively
    xivelyclient.put returned -1
    HTTP Error
    Sending RSSI to Xively:  -27
    Sending Temp to Xively:  154.33
    Sending Ph to Xively:  6.94
    Sending ORP to Xively:  0.87
    Uploading it to Xively
    xivelyclient.put returned -1
    HTTP Error
    Sending RSSI to Xively:  -27
    Sending Temp to Xively:  147.25
    Sending Ph to Xively:  6.94
    Sending ORP to Xively:  0.83
    Uploading it to Xively
    No Socket available
    xivelyclient.put returned -1
    No Socket available
    HTTP Error
    Sending RSSI to Xively:  -27
    Sending Temp to Xively:  149.91
    Sending Ph to Xively:  6.94
    Sending ORP to Xively:  0.87
    Uploading it to Xively
    No Socket available
    xivelyclient.put returned -1
    No Socket available
    HTTP Error

Answer 1

Thanks for providing so much background on your question, it made it easy to test and figure out what your issue is. As long as you are connecting to your wifi ok, it looks like your code should be good to go except for all the imports. All I did was remove the extra imports you had at the beginning. Regarding setting your own DNS server, you can do this but this may have been what was causing your issues. If you are worried about DNS you are better of setting the IP manually and not relying on DNS.

Below is my reworked version of what I copied from your code. Hopefully it will work with your network and feed. I tested it on an UNO and Mega ADK (only Mega I had) with official Arduino WiFi shield and it worked on both.

// Libraries in use
#include <SPI.h>
#include <WiFi.h>
#include <HttpClient.h>
#include <Xively.h>
/*
     Hot Tub Monitor 
         --- If you are only calibrating your sensor, use the calibrate sensor script.  This is for submerged operation.
     This script will allow you to test to ensure the temp, Ph, and ORD sensors are operating and are calibrated correctly.----

     This script was written for the MEGA 2560 with the wireless shield, connecting in to Xively's cloud graph service

     The Mega 2560 with the Wireless shield and Probes uses the following pins:
     *  SPI bus interface 
     *  Onboard MicroSD card reader (uses SD Lib) on digital pin 4
     *  Digital Pins 7, 50, 51, 52, and 53 are reserved and shouldn't be used
     *  Digital Pin 18 is set to OUTPUT to power the temp probe on/off 
     *  Atlas Scientific Temp Sensor input on Analog Uno pin A4
     *  Phidgets Ph Sensor input on Analog Uno pin A2
     *  Phidgets ORD Sensor input on Analog Uno pin A0
*/


// setting up some of the globals
const int TEMPPIN = 4;
const int PHPIN = 1;
const int ORPPIN = 0;
boolean isDebugEnabled = true;   //setting up the debug state
int status = WL_IDLE_STATUS;
char ssid[] = "LMI-GUEST"; //  your network SSID (name) 
char pass[] = "2009LMIGuest!";    // your network password (use for WPA, or use as key for WEP)

// My Xively key to let you upload data
char xivelyKey[] = "<snip for security>";
// My xively feed ID
#define xivelyFeed 121601
// My datastreams
char myWirelessStrStream[] = "MonitorWirelessStrength";
char myORPStream[] = "ORP";
char myPhStream[] = "Ph";
char myTempStream[] = "Temp";

// Creating the datastreams
XivelyDatastream datastreams[] = {
    XivelyDatastream(myWirelessStrStream, strlen(myWirelessStrStream), DATASTREAM_FLOAT),
    XivelyDatastream(myORPStream, strlen(myORPStream), DATASTREAM_FLOAT),
    XivelyDatastream(myPhStream, strlen(myPhStream), DATASTREAM_FLOAT), 
    XivelyDatastream(myTempStream, strlen(myTempStream), DATASTREAM_FLOAT)
    };
XivelyFeed feed(xivelyFeed, datastreams, 4);

//starting the Xively client
WiFiClient client;
XivelyClient xivelyclient(client);


void setup() {
  if (isDebugEnabled) {   //setting up the debug stream
    Serial.begin(9600);
    Serial.println("Hot Tub Monitor Debug Stream Starting");
    Serial.println("-----------------------------------");
  }
  pinMode(12,OUTPUT);   //this pin turns on the temp sensor - battery saver to have this on/off switchable

  // connect to the wifi
  // check for presence of the shield
  if (WiFi.status() == WL_NO_SHIELD) {
    Serial.println("WiFi shield not present"); 
    // don't continue:
    while(true);
  } 

  //Connect to the wifi network
    while ( status != WL_CONNECTED) { 
      Serial.print("Attempting to connect to WPA SSID: ");
      Serial.println(ssid);
      // Connect to WPA/WPA2 network:    
      status = WiFi.begin(ssid, pass);

      // wait 10 seconds for connection:
      delay(10000);
  }
  Serial.println("You're connected to the network");
  Serial.println(status);
  //printCurrentNet();
  printWifiData();

  // print the received signal strength:
  long rssi = WiFi.RSSI();
  Serial.print("signal strength (RSSI):");
  Serial.println(rssi);

}

void loop() {
// report on the WiFi Signal strength  
   long rssi = WiFi.RSSI();
  if (isDebugEnabled) {   //send the signal str to Xively
    Serial.print("Sending RSSI to Xively:  ");
    Serial.println(rssi);
  }
    // print the received signal strength:
  datastreams[0].setFloat(rssi);

//  get the temp from our Atlas Sci probe
  float tempC=get_temp();
  float tempF = (tempC*1.8)+32;
  datastreams[1].setFloat(tempF);

// debugging info for temp
  if (isDebugEnabled) {   //send the temp to Xively
    Serial.print("Sending Temp to Xively:  ");
    Serial.println(tempF);
  }

// get the Ph from our phidget's monitor  
  float Ph=get_Ph(tempC);
  datastreams[2].setFloat(Ph);

// debugging info for Ph
  if (isDebugEnabled) {   //send the Ph to Xively
    Serial.print("Sending Ph to Xively:  ");
    Serial.println(Ph);
  } 

// get the Ph from our phidget's monitor  
  float ORP=get_ORP();
  datastreams[3].setFloat(ORP);

// debugging info for Ph
  if (isDebugEnabled) {   //send the Ph to Xively
    Serial.print("Sending ORP to Xively:  ");
    Serial.println(ORP);
  } 


  Serial.println("Uploading it to Xively");
  int ret = xivelyclient.put(feed, xivelyKey);
  Serial.print("xivelyclient.put returned ");
  Serial.println(ret);


   delay(10000);
}  
float get_Ph(float tempC) {  
  float Ph = analogRead(PHPIN);
  Ph = 7 -((2.5 - (Ph/200))/((0.257179 + 0.0000941468)*tempC));  // convert to the ph
  return Ph;
  }

float get_ORP() {
  float ORP = analogRead(ORPPIN);
  ORP = (2.5 - (ORP/200))/1.037;  // convert to proper ORP
  return ORP;
  } 

 float get_temp(){      
  float v_out;
  float Temp;
  digitalWrite(A4, LOW);   //wtf is this for?
  digitalWrite(12, HIGH);
  delay(2);
  v_out = analogRead(4);
  digitalWrite(12, LOW);
  v_out*=.0048;
  v_out*=1000;
  Temp=0.0512 * v_out -20.5128;
  return Temp;
}

void printWifiData() {
  // print your WiFi shield's IP address:
  IPAddress ip = WiFi.localIP();
  Serial.print("IP Address: ");
  Serial.println(ip);
  Serial.println(ip);
}

Hope this helps.