How to send data to the cloud service Ubidots from a Sky mote using Contiki-OS?

Objective

I have a sensor node CM5000, which is compatible with a sky mote, and want to use it to send temperature data to the cloud service Ubidots. Currently, the node is working with the operating system Contiki-OS, specifically i am working with Instant-contiki-3.0.

I did some research and the web page below gives you the steps to send temperature data to Ubidots using a Z1 mote. I follow the steps of the web page, but since the sky mote is not compatible with a Z1 mote then it does not work.

http://wireless.ictp.it/school_2015/book/#_sending_data_to_ubidots

Here, i will show you how to send data to Ubidots using Sky motes modifying the code from the web page above.

Step 1: Create an account in Ubidots

• Create a Data Source by clicking

  Sources -> Add Data Source -> Generic -> Create
  

  Now, you must have a data source named My Datasource.

• Create a variable by clicking

  Sources -> My Datasource -> Add Variable -> Name = Temperature -> Create
  

  Now, you must have a variable named Temperature.

• Keep in mind the variable's ID: Click in

  Sources -> My Datasource 
  

  Each variable at the top right-hand corner have an i, and if you click it, then it will show you the variable's ID. My variable's ID is:

  567a05d07625424d60d32a31 
  

• Keep in mind your API Key: Click in

  My Profile -> API Keys
  

  There you will find your API Key. My API Key is:

  2eed47ae4097bbbfd26ae57c8eb799cc450d0416 
  

• Create a Dashboard by clicking

  Dashboard -> + -> Line Chart -> My Datasource -> Temperature -> Finish
  

Step 2: Create the serial-ubidots App

• Go to the folder /contiki-3.0/apps

  cd /home/user/contiki-3.0/apps
  

• Create a folder named serial-ubidots
• Within that folder, you must create a Makefile named Makefile.serial-ubidots with the following code in it:

  serial-ubidots_src = serial-ubidots.c
  

• Within that folder, you must create a file named serial-ubidots.c with the following code in it:

  #include 
  #include "serial-ubidots.h"
  void
  send_to_ubidots(const char *api, const char *id, uint16_t val) // api = API KEY, ID = Variable's ID, Val = Value of temperature
  {
      unsigned char buf[6];
      snprintf(buf, 6, "%d", val); 
      printf("***%s\t", api); // The *** indicate the start of the data sent to Ubidots
      printf("%s\t", id);
      printf("%s***\n", buf); // The *** indicate the end of the data sent to Ubidots
   }
  

• Within that folder, you must create a file named serial-ubidots.h with the following code in it:

  #define VAR_LEN 24
   #define UBIDOTS_MSG_LEN (VAR_LEN + 2)
   struct ubidots_msg_t {
     char var_key[VAR_LEN];
     uint8_t value[2];
   };
   void send_to_ubidots(const char *api, const char *id, uint16_t val);
  

• Include the serial-ubidots App in the makefile of sky motes: Go to the folder /home/user/contiki-3.0/examples/sky

  cd /home/user/contiki-3.0/examples/sky
  

  Open the Makefile and add the following line

  APPS=serial-ubidots
  

  Now, the Makefile should look like this

  CONTIKI = ../..
  ifndef TARGET
  TARGET=sky
  endif
  
  all: blink sky-collect #rt-leds test-button test-cfs tcprudolph0
  
  APPS=serial-ubidots
  
  %.tgz: %.ihex
      mkdir $(basename $<) ; \
      mv $< $(basename $<) ; \
      echo $(basename $<)/$(basename $<).ihex 600 > $(basename $<)/runfile ; \
      tar czf $@ $(basename $<)
  
  CONTIKI_WITH_IPV4 = 1
  CONTIKI_WITH_RIME = 1
  include $(CONTIKI)/Makefile.include
  

Step 3: Create a contiki C file that reads the temperature and send it to the serial port via the serial-ubidots app previously created

• Go to the folder /home/user/contiki-3.0/examples/sky

  cd /home/user/contiki-3.0/examples/sky
  

  Create a file named temperature.c with the following code in it

  
  #include "contiki.h"
   #include "dev/sht11/sht11-sensor.h"
   #include "dev/light-sensor.h"
   #include "dev/leds.h"
   #include 
   #include "serial-ubidots.h"
  
   //Declare the process
   PROCESS(send_sensor_info_process, "Print the Sensors Information");
  
  //Make the process start when the module is loaded
  AUTOSTART_PROCESSES(&send_sensor_info_process);
  
  static uint16_t 
  get_temp(void)
  {
    return ((sht11_sensor.value(SHT11_SENSOR_TEMP) / 10) - 396) / 10;
  }
  /*---------------------------------------------------------------------------*/
  
  //Define the process code
  PROCESS_THREAD(send_sensor_info_process, ev, data)
  {
  
    static struct etimer et;
    static const char api_key[] = "2eed47ae4097bbbfd26ae57c8eb799cc450d0416"; // This is your API Key previously copied from Ubidots
    static const char var_key[] = "567a05d07625424d60d32a31"; // This is your variable's ID previously copied from Ubidots
  
    PROCESS_BEGIN();
  
    uint16_t  raw;
  
    while(1){
      etimer_set(&et, CLOCK_SECOND * 15);
      SENSORS_ACTIVATE(sht11_sensor);
      PROCESS_WAIT_EVENT_UNTIL(etimer_expired(&et));
      raw = get_temp() ;
      send_to_ubidots(api_key, var_key, raw);
      etimer_reset(&et);
      SENSORS_DEACTIVATE(sht11_sensor);
   }
    PROCESS_END();
  } 
  
  

• Upload the temperature.c code into the sky mote and login with the following command:

  make TARGET=sky temperature.upload && make login
  

  Then, you should be able to see this in the terminal every 15 seconds

  ***2eed47ae4097bbbfd26ae57c8eb799cc450d0416 567a05d07625424d60d32a31    29***
  

  That means that the sky mote is sending over the /dev/ttyUSB0/ the following information

          *** = Indicates start of frame
          2eed47ae4097bbbfd26ae57c8eb799cc450d0416 = Api Key
          \t = Tab key to separate data 
          567a05d07625424d60d32a31 = Variable's ID
          \t = Tab key to separate data
          29 = Temperature (Celsius) 
          *** = Indicates end of frame
  

Step 4: Create a Python Script to read the data from the serial port and send it to Ubidots

• Install Python in your computer

  sudo apt-get install build-essential checkinstall
   sudo apt-get install libreadline-gplv2-dev libncursesw5-dev libssl-dev libsqlite3-dev tk-dev libgdbm-dev libc6-dev libbz2-dev
   cd ~/Downloads/
   wget http://python.org/ftp/python/2.7.5/Python-2.7.5.tgz
   tar -xvf Python-2.7.5.tgz
   cd Python-2.7.5
   ./configure
   make
  

• Install pip in Linux

   sudo easy_install pip
  

• Install the Python library Ubidots for python

   sudo pip install ubidots==1.6.1
  

• Go to the folder /home/user/contiki-3.0/examples/sky

   cd /home/user/contiki-3.0/examples/sky
  

• Create a file named UbidotsPython.py with the following code in it:

  # -*- coding: utf-8 -*-
   # ----------------------------------------------------------------------------#
   # Simple application to relay data to Ubidots from a Contiki serial-based conn
   # ----------------------------------------------------------------------------#
  
  
   import serial
   from time import sleep
   from ubidots import ApiClient
  
   # Use as default
   PORT = "/dev/ttyUSB0"
  
   # ----------------------------------------------------------------------------#
   # Create a serial object and connect to mote over USB
   # ----------------------------------------------------------------------------#
   def connectMote(port):
     try:
       ser = serial.Serial(port, 115200,timeout=0, parity=serial.PARITY_NONE,
                 stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS)
     except:
       sys.exit("Error connecting to the USB device, aborting")
     return ser
  
     # ----------------------------------------------------------------------------#
     # Parse the serial data and publish to Ubidots, this assumes the following:
     # \r\n API_KEY \t VAR_KEY \t VALUE \r\n
     # ----------------------------------------------------------------------------#
     def process_data(raw):
  
     # Search for start and end of frame and slice, discard incomplete
  
     if "***" in raw:
      raw = raw[(raw.index("***") + 3):]
  
      if "***" in raw:
        raw = raw[:raw.index("***")]
  
        # We should have a full frame, parse based on tab and create a list
        ubidots_raw = raw.split("\t")
        # Create a Ubidots client and get a pointer to the variable
        client = ApiClient(ubidots_raw[0])
        try:
          my_variable = client.get_variable(ubidots_raw[1])
        except Exception, e:
          print "Ubidots error: %s" % e
          return
        # Update the variable
        my_variable.save_value({'value':int(ubidots_raw[2])})
  
   # ----------------------------------------------------------------------------#
   # MAIN APP
   # ----------------------------------------------------------------------------#
   if __name__=='__main__':
  
     # Create the serial object and connect to the mode
     # Do not check the serial port object as the function already does it
     s = connectMote(PORT)
  
     # Loop forever and wait for serial data
     while True:
       queue = s.inWaiting()
       if queue > 0:
         data = s.read(1000)
         process_data(data)
       sleep(0.2)
  

Step 5:Send data to Ubidots

• Go to the folder /home/user/contiki-3.0/examples/sky

   cd /home/user/contiki-3.0/examples/sky
  

• Upload the temperature.c code

   make TARGET=sky temperature.upload
  

• Execute the script UbidotsPython.py

   python UbidotsPython.py
  
  

  Wait approximately 15 seconds for the first data to appear in the dashboard of Ubidots.