PROGRAMMING THE BOARD

For programming my board for the sensor,I used arduino IDE.In Aurdino first we have to select the programmer,board,processor and the clock before writing the program.For my board the details are as follows:

programmer- USBtiny
Board-ATtiny 25/45/85
Proces MHz internal
I reffered many programs using Arduino and HC-SR04 sensor in the internet.I came across a program in Instructables for measuring the distance using HC-SR04 sensor.Firstly,I did a program which can make use of my leds which I designed in my board.The program is written is such a way that the red led will light upto 10 cm and from 10 to 100 cm orange led will lit up.After that again the red led lights up.The code is as follows:

                


                   #define trigPin A2//defining trigpin to A2/PB4
                   #define echoPin A3//defining echopin to A3/PB3
                   #define led PB1//defining led to PB1
                   #define led2 PB0//defining led2 to PB0

                   void setup() {
                   pinMode(trigPin, OUTPUT);
                   pinMode(echoPin, INPUT);
                   pinMode(led, OUTPUT);
                   pinMode(led2, OUTPUT);
                    }

                   void loop() {
                   long duration, distance;
                   digitalWrite(trigPin, LOW);//setting trigpin to low
                   delayMicroseconds(2);
                   digitalWrite(trigPin, HIGH);//setting trigpin to low
                   delayMicroseconds(10);
                   digitalWrite(trigPin, LOW);
                   duration = pulseIn(echoPin, HIGH);
                   distance = (duration/2) / 29.1;//soundwave speed-distance conversion
                   if (distance < 10) //less than 10cm
                   {
                        digitalWrite(led2,HIGH); // Red led goes on
                        digitalWrite(led,LOW);  // orange led goes off
                   }
                   else if (distance >= 100 || distance <= 0)
                   {
                       digitalWrite(led2,HIGH); // Red led goes on
                       digitalWrite(led,LOW);  // orange led goes off
                   }
                  else //between 10cm to 100cm
                   {
                       digitalWrite(led2,LOW);// Red led goes off
                       digitalWrite(led,HIGH);// orange led goes on
                   }

                   delay(500);
                    }

               }

After programing I have read my sensor with the help of a measurement tape and it was close enough.The video is shown below:

After this program I have modified the Instructables program to read the output of the sensor from arduino serial monitor.The program is as follows:

                   


                   #include 
                   SoftwareSerial serial(A1, 1);//rx pin of ftdi header as receiver and mosi as tx
                   const int trigPin = A2;  // defines pins numbers
                   const int echoPin = A3;  // defines pins numbers
                   long duration;  // defines variables
                   int distance;   // defines variables
                   void setup()
                   {
                    pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
                    pinMode(echoPin, INPUT); // Sets the echoPin as an Input
                    serial.begin(9600); // Starts the serial communication
                   }
                  void loop()
                  {

                   digitalWrite(trigPin, 0);// Clears the trigPin
                   delayMicroseconds(2000);
                   digitalWrite(trigPin, 1);
                   delayMicroseconds(5); // Sets the trigPin on HIGH state for 5 micro seconds
                   digitalWrite(trigPin, 0);
                   duration = pulseIn(echoPin, 1); // Reads the echoPin, returns the sound wave travel time in microseconds
                   distance = duration * 0.034 / 2; // Calculating the distance
                   if
                   (distance > 100)
                    {
                     serial.println("out of range");
                    }
                  else
                   {
                    serial.print("Distance: "); // Prints the distance on the Serial Monitor
                    serial.print(distance);// Prints the distance on the Serial Monitor
                    serial.println(" Cm");// Prints the distance on the Serial Monitor
                   }
                  delay(2000);
                  }

                  

SERIAL MONITOR OUTPUTS

Group Assignment

In group assignment we have to measure the analog and digital signals in an input device (we are using sensor). Usually a microcontroller takes two types of input analog and digital and so we are asked to measure these.Sensors can be of digital and analog type.
For analog level measurement we used a LDR sensor

sensor connected to the board

Digital Sensor produce discrete values of 0 and 1. Discrete values often called digital (binary) signals in digital communication. For digital signal measurement we are using Arduino connected with PIR sensor.

sensor connected to the board