Networking and Communications


Assignment Requirements:

  • Group Assignment:
  • Individual Assignment:

    • Learning Outcomes:

  • Demonstrate workflows used in network design.
  • Implement and interpret networking protocols and/or communication protocols.

    • Steps in General:

    Introduction

    In this week I decided to make a wired communication using the UART method, I desiged a bridge and 2 nodes, programed each circuit and did the communication well.

    Steps in Details:

    Step(1): Designing the circuits on KiCAD

    Step(2): Preparing the png files on Gerbv and GIMP

    Step(3): PCB Fabrication, Assembly and Soldering

    Step(4): Circuit Programming and Testing

    Group Assignment

    Ways of Communications

    Introduction

    Embedded electronics is all about interlinking circuits (processors or other integrated circuits) to create a symbiotic system. In order for those individual circuits to swap their information, they must share a common communication protocol. Hundreds of communication protocols have been defined to achieve this data exchange, and, in general, each can be separated into one of two categories: parallel or serial.

    Parallel vs. Serial

    Parallel interfaces transfer multiple bits at the same time. They usually require buses of data - transmitting across eight, sixteen, or more wires. Data is transferred in huge, crashing waves of 1's and 0's.

    Serial interfaces stream their data, one single bit at a time. These interfaces can operate on as little as one wire, usually never more than four.

    Parallel communication certainly has its benefits. It's fast, straightforward, and relatively easy to implement. But it requires many more input/output (I/O) lines. If you've ever had to move a project from a basic Arduino Uno to a Mega, you know that the I/O lines on a microprocessor can be precious and few. So, we often opt for serial communication, sacrificing potential speed for pin real estate.

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    Asynchronous Serial

    Asynchronous means that data is transferred without support from an external clock signal. This transmission method is perfect for minimizing the required wires and I/O pins, but it does mean we need to put some extra effort into reliably transferring and receiving data.

    The asynchronous serial protocol has a number of built-in rules - mechanisms that help ensure robust and error-free data transfers, such as:

    Wiring and Hardware: A serial bus consists of just two wires - one for sending data and another for receiving. As such, serial devices should have two serial pins: the receiver, RX, and the transmitter, TX.
    It's important to note that those RX and TX labels are with respect to the device itself. So the RX from one device should go to the TX of the other, and vice-versa. It's weird if you're used to hooking up VCC to VCC, GND to GND, MOSI to MOSI, etc., but it makes sense if you think about it. The transmitter should be talking to the receiver, not to another transmitter.



    UARTs
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    Serial Peripheral Interface (SPI)
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    Inter-Integrated Circuit (I2C)
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    I2C vs SPI
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    Implementation

    Introduction
    Programming the WIFI Board
           

// Including Libraries
#define DEBUG 1
#include 
#include 
#include 



//FIXED WIFI Settings 
#define ssid      "Orange-D955"       // WiFi SSID
#define password  "IloveFLE"  // WiFi password



// FIXED IP and NETWORK SETTINGS
IPAddress ip(192, 168, 1, 104);
//set static ip
IPAddress gateway(192, 168, 0, 1);
//set gateway
IPAddress subnet(255, 255, 255, 0);
//set subnet
ESP8266WebServer server ( 80 );



// INVENTORY ITEM NAMES, COUNT and QUANTITY
#define numberOfItems 12
String item[numberOfItems] = {
  "ATtiny44",
    "ATtiny45",
    "20MHz_Oscillator",
    "10k_Resistor",
    "499_Resistor",
    "LED_Red",
    "LED_Blue",
    "ATMega328p",
    "1uF_Capacitor",
    "Push_Buttons",
    "AVR_ISP_Header",
    "Male_Header_Pins"
}
;
byte itemQty[numberOfItems]  = {
  0,0,0,0,0,0,0,0,0,0,0,0
}; // DUMMY VARIABLE for storage
byte itemQtyS[numberOfItems] = {
  10,13,5,18,6,9,3,2,12,14,16,20
}; // INITIAL COUNT when there is nothing in EEPROM, this is already saved now



// WEBPAGE CODE
// code was tested with notepad and browser(chrome)
// code written with help from bootstrap online demos and tutorials
// once code was ready, changed all double quotes to single quotes
// added variables for dynamic web page generation
String getPage(int boxNumber) {
  String page = "< html lang='en'>";
  page += "< html lang='en'>";
  page += "< head>";
  page += "< meta charset='utf-8'>";
  page += "< meta http-equiv='X-UA-Compatible' content='IE=edge'>";
  page += "< meta name='viewport' content='width=device-width, initial-scale=1'>";
  page += "< title>Smart Drawer< /title>";
  page += "< meta name='author' content='LayoutIt!'>";
  page += "< link rel='stylesheet' href='https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css'>";
  page += "< script src='https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js'>< /script>";
  page += "< script src='https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js'>< /script>";
  page += "";
  page += " < body>";
  page += "< div class='container-fluid'>";
  page += "  < div class='row'>";
  page += "   < div class='col-md-12'>";
  page += "     < p>";
  page += "     < /p>";
  page += "   < /div>";
  page += " < /div>";
  page += " < div class='row'>";
  page += "   < div class='col-md-12'>";
  page += "     < div class='jumbotron'>";
  page += "       < h2>";
  page += "       Smart Drawer< /h2>";
  page += "       < h3>";
  page += "       Find and store components smartly< /h3>";
  page += "       < p>";
  page += "          Please type the component name in the below box";
  page += "       < /p>";
  // SERACH BOX CODE - now removed.
  //page += "        < p>";
  //page += "         < form role='form' action='/' method='POST' class='form-inline'>";
  //page += "           < div class='form-group'>";
  //page += "             < label for='componentLabel'>";
  //page += "             SEARCH HERE: < /label>";
  //page += "             < input class='form-control' id='componentLabel' name='searchText'>";
  //page += "           < /div>";
  //page += "           < button type='submit' class='btn btn-primary'>";
  //page += "           Submit < /button>";
  //page += "         < /form>";
  //page += "       < /p>";
  page += "       < div class='row' style='margin-bottom:15px;'>";
    page += "         < form role='form' action='/' method='POST' class='form-inline'>";
    page += "           < div class='form-group'>";
    page += "             < label>Component Name:< /label>";
    page += "             < input type='text' id='search' name='search'>";
    page += "           < /div>";
    page += "         < button type='submit' class='btn btn-primary'>Search< /button>";
    page += "         < /form>";

  if(boxNumber != -1)
  {
    page += "< div class='col-sm-4'>";
    page += "< button type='button' class='btn btn-block btn-primary btn-lg' data-toggle='modal' data-target='#";
    page += item[boxNumber];
    page += "'>";
    page += item[boxNumber];
    page += " - Qty: ";
    page += String(int(itemQty[boxNumber]));
    page += "< /button>< /div>";

    // Loop to generate code for MODAL/POPUP Boxes that appear when any button is clicked
    // Generated DYNAMICALLY from variables in code
      page += "< div id='";
      page += item[boxNumber];
      page += "' class='modal fade' role='dialog'>";
      page += "  < div class='modal-dialog'>";
      page += "    < div class='modal-content'>";
      page += "      < div class='modal-header'>";
    page += "        < button type='button' class='close' data-dismiss='modal'>×";
    page += "        < h4 class='modal-title'>";
    page += item[boxNumber];
    page += "< /h4>";
    page += "      < /div>";
    page += "      < div class='modal-body'>";
    page += "        < p>The Quantity of this item is = ";
    page += String(int(itemQty[boxNumber]));
    page += "        < /p>";
    page += "       < p>";
    
    page += "         < form role='form' action='/' method='POST' class='form-inline'>";
    page += "           < div class='form-group'>";
    page += "             < label>Enter Quantity:";
    page += "             < input type='number' class='form-control bfh-number' data-zeros='true' value='0' name='qtyChange' />";
    page += "             < label class='radio-inline'>< input type='radio' name='add'>ADD< /label>";
    page += "             < label class='radio-inline'>< input type='radio' name='remove'>REMOVE";
    page += "             < input type='hidden' name='itemNumber' value='";
    page += String(boxNumber);
    page += "             '/>";
    page += "           < /div>";
    page += "         < button type='submit' class='btn btn-primary'>LOCATE COMPONENT";
    page += "         < /form>";
    page += "        < /p>";
    page += "      < /div>";
    page += "    < /div>";
    page += "  < /div>";
    page += "< /div>";
  }
  page += "     < /div>";
  page += "   < /div>";
  page += " < /div>";
  page += "< /div>";
  page += "< /body>";
  page += "< /html>";
  return page;
}

// function which manages how the page is shown to user and what operation is perfomed for inventory control.
void handleRoot() {
  int itemNumber = 100, qtyChange = 0, sign = 1;
  String search_value = "";
  boolean search_v = false;
  int search_index = -1;
  if (server.args() > 0 ) {
    if(DEBUG)
      Serial.println("Server Arguments: ");
    for ( int i = 0; i < server.args(); i++ ) {
      if(DEBUG){
        Serial.print(server.argName(i));
        Serial.print(": ");
        Serial.println(server.arg(i));
      }
      if (server.argName(i) == "search")
      {
                search_value = server.arg(i);
                search_v = true;
      }      
      if (server.argName(i) == "qtyChange")
                qtyChange = server.arg(i).toInt();
      if (server.argName(i) == "itemNumber")
                itemNumber = server.arg(i).toInt();
      if (server.argName(i) == "add")
                sign = 1;
      if (server.argName(i) == "remove")
                sign = -1;
      // if server argument is a valid add/remove number
      // the item quantity is changed, saved in variable, showed to user and saved in EEPROM
      if(itemNumber < numberOfItems) {
        if(itemQty[itemNumber]+(qtyChange*sign)>=0){
          itemQty[itemNumber] = itemQty[itemNumber]+(qtyChange*sign);
          EEPROM.write(itemNumber, itemQty[itemNumber]);
          EEPROM.commit();
        }
        Serial.println(itemNumber);
        Serial.println(",");
      }
    }
  }
  if(search_v)
  {
    for (int z=0; z< numberOfItems; z++) 
    {
      if(search_value == item[z])
      {
        search_index = z;
        break;
      }
    }

  server.send ( 200, "text/html", getPage(search_index));

  }
  else
    server.send ( 200, "text/html", getPage(-1) );
}

int address = 0;
byte value;
void setup() {
    // INITIALIZATION CODE, Serial, EEPROM, Server
  delay(1000);
  EEPROM.begin(512);
  Serial.begin(115200);
  delay(1000);
  Serial.println(-1);
  delay(1000);
  Serial.println(-1);
  // WRITE ALL DEFAULT VALUES TO EEPROM
  //  Serial.println("itemQtyS[z]");
  //  for(int z=0; z< numberOfItems; z++){
  //    address = z;
  //    EEPROM.write(address, itemQtyS[z]);
  //    Serial.println(itemQtyS[z]);
  //    address  = address  + 1;
  //    if (address  == 512)
  //    {
  //      address  = 0;
  //      EEPROM.commit();
  //    }
  //  }
    // READ ITEM QUANTITY from EEPROM
  if(DEBUG)
    Serial.println("itemQtyREAD[z]");
  for (int z=0; z< numberOfItems; z++) {
    address = z;
    itemQty[z] = EEPROM.read(address);
    if(DEBUG)
      Serial.println(itemQty[z]);
    address  = address  + 1;
    if (address  == 512) {
      address  = 0;
      EEPROM.commit();
    }
  }



// connect to WIFI and start WEB SERVER
  if(DEBUG) {
    Serial.println();
    Serial.println();
    Serial.print("Connecting to ");
    Serial.println(ssid);
  }
  WiFi.config(ip, gateway, subnet);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    if(DEBUG)
          Serial.print(".");
  }
  if(DEBUG) {
    Serial.println("");
    Serial.println("WiFi connected");
  }
  delay(1000);
  Serial.println(0);
  server.begin();
  if(DEBUG) {
    Serial.println("Server started");
    Serial.print("Type this address in URL to connect: ");
    Serial.print("http://");
    Serial.println(ip);
    Serial.println("/");
  }


  
  // link to the function that manage launch page 
  server.on ( "/", handleRoot );
  server.begin();
  delay(1000);
  Serial.println(1);
  if(DEBUG)
    Serial.println ( "HTTP server started" );
  delay(1000);
  Serial.println(2);
  delay(1000);
  Serial.println(-1);
  delay(1000);
  Serial.println(-1);


  
  // TURN OFF ALL LEDS
  // at start LEDs of boxes 1, 2 and 3 are turned on to indicate system status
  // each step makes the other box LEDs turn on
  // box 2 is wifi connected status
  // box 3 is server start status
}
void loop() {
  server.handleClient();
  delay(500);
}

// LOOP code, keeps running forever.



// Original checked by Noor
// edited by Mahmoud Abo Elnaga
    Programming the Controller Board
           

// Including Libraries
#include "FastLED.h"
#define NUM_LEDS 20 
CRGB leds[NUM_LEDS];
#define PIN 6 



// variable for which BOX LEDs to blink
byte ledToBlink = 0;


void setup()
{
  Serial.begin(115200);
  FastLED.addLeds(leds, NUM_LEDS).setCorrection( TypicalLEDStrip );
}
//Initialization PART.
// Starts the Serial Port, Controller waits for a NUMBER on the Serial Port to turn on the relevant LEDs of the selected BOX.



// RGB LED SUPPORT FUNCTIONS - from blog link: https://www.tweaking4all.com/hardware/arduino/adruino-led-strip-effects/
void showStrip() {
 #ifdef ADAFRUIT_NEOPIXEL_H 
   // NeoPixel
   strip.show();
 #endif
 #ifndef ADAFRUIT_NEOPIXEL_H
   // FastLED
   FastLED.show();
 #endif
}



// RGB LED SUPPORT FUNCTIONS - for a single PIXEL - from blog link: https://www.tweaking4all.com/hardware/arduino/adruino-led-strip-effects/
void setPixel(int Pixel, byte red, byte green, byte blue) {
 #ifdef ADAFRUIT_NEOPIXEL_H 
    // NeoPixel
   strip.setPixelColor(Pixel, strip.Color(red, green, blue));
 #endif
 #ifndef ADAFRUIT_NEOPIXEL_H 
   // FastLED
   leds[Pixel].r = red;
   leds[Pixel].g = green;
   leds[Pixel].b = blue;
 #endif
}



// RGB LED SUPPORT FUNCTIONS - for all LEDs - from blog link: https://www.tweaking4all.com/hardware/arduino/adruino-led-strip-effects/
void setAll(byte red, byte green, byte blue) {
  for(int i = 0; i < NUM_LEDS; i++ ) {
    setPixel(i, red, green, blue); 
  }
  showStrip();
}


// LED EFFECT FUNCTION - from blog link: https://www.tweaking4all.com/hardware/arduino/adruino-led-strip-effects/
// MODIFIED to read SERIAL and ONLY show the relevant LED and the one before and after it.
// Each box has 3 LEDs, so the number received is multiplied by 3 and then the LED before it and after it is illuminated and rest are all set as color to BLACK.
void RunningLights(byte red, byte green, byte blue, int WaveDelay) {
  int Position=0;
  for(int i=0; i0){
          // ONLY TURN ON 3 LEDs and rest all set to BLACK==OFF
          //if(i==ledToBlink-3 || i==ledToBlink-2 || i==ledToBlink-1)
          if( i==ledToBlink-1 )
           setPixel(i,((sin(i+Position) * 127 + 128)/255)*red,
           ((sin(i+Position) * 127 + 128)/255)*green,
           ((sin(i+Position) * 127 + 128)/255)*blue);
          else
            leds[i] = CRGB::Black;
        }else{
            leds[i] = CRGB::Black;          
        }
      }
      // CODE MODIFICATION END
      
      showStrip();
      delay(WaveDelay);
  }
}

// LOOP FUNCTION, keeps the led effect running at all times
// LED effect changes color.
void loop() {
  RunningLights(0xff,0,0, 50);        // red
  RunningLights(0,0xff,0, 50);        // green
  RunningLights(0,0,0xff, 50);        // blue
  RunningLights(0xff,0xff,0xff, 50);  // white
  // original checked by Noor
  // further edits by Mahmoud Abo Elnaga
}
    Wiring
    • I connected the TX of the WIFI board to the RX of the Controller board.
    • Connected the VCC and GND of the WIFI board to the VCC and GND of the Controller board. Both are operated at 5 VDC.
    • Connected the addressable pin of the RGB led with Pin#6 of the controller board.
    • Powered up the boards with 5 VDC and the RGB LED Strip with 12 VDC.
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    Results

    • I connected the boards with the RGB LED Strip in the structure.
    • Opened the IP address on my mobile phone and started typing the component name.
    • Please note that Week 12, 13 and final project pages are integrating, they complete each other.

  • We also did another project in which we are tried to communicate between two devices. The communication is a wired communication utilizing UART on both devices. The devices chosen are two arduino boards, one is connected to a switch and the other is connected to an LED. When the switch is pressed on one device, it sends a message to the other device telling it to switch the LED on and off when the swtich is unpressed.
  • All the documentation is in the group assignment page.

    • Downloads:

    UART Communication Files.rar Group Assignment Files.rar