ARDUINO DEVELOPMENT BOARD BASICS PART 2

            Lets continue talking about Arduino IDE. Arduino is a powerful solution for newbies. Let us discuss about a simple program. First open Arduino IDE and follow the path given below

File > Examples > Basics > DigitalReadSerial

It should open in a new program window as shown below 

            In the starting of the program  we can see a short description about the program followed by /* and */  indicates that it is a multi line comment which not considered during the execution of the program .  Also following that you can find a description followed by // which indicates they are single line comments. You can use these techniques to add important comments to your program.

            In the beginning of the program you can see that 

int pushButton =  2;

By closely observing the code you can find that the int is highlighted which means it is a function. int means that the function is an integer. Following that the word pushButton is a variable. The variable is just a word which holds the data provided by the = sign. You can set any name to a variable. Here = 2 indicates  it id digital pin 2 on the Arduino board. At the end of each statement it ends with ; which means that you are done with that function. You should provide ; to ending of each function.

Following that we have already discussed that the functions void setup() and void loop() are essential in writing the program code. void means that that function do not return any information back to the  program. The function setup() run only once in the program. But in the case of loop() which runs over and over in the program.

          The delay() function indicates the rate or speed of the process. It is expressed in milliseconds.  For example if we want to blink an led every second, after we turn it on we can place a delay(1000) which will make the processor sit there and do nothing for a second (1000 milliseconds). Delay is also useful in debugging and general flow control.

ARDUINO DEVELOPMENT BOARD BASICS PART 1

           An Arduino is a physical hardware which is very useful for electronic projects. The heart of an Arduino is a microcontroller chip which can be programmed by C programing language. It is very cheap and compact in size which can be very useful in robotics projects. There are various type of Arduino boards are available in the market such as Arduino uno, Mega, Nano...etc

             Talking about Arduino it consists of several connection pins as shown in the figure.  An Arduino can be used to analog to digital conversion and vice versa. As yo can see in the figure the left side pins A0 to A5 are analog pins and the right hand side consist of digital pins. The Arduino can itself provide  a constant DC voltage of 3.3V and 5V.

             An Arduino can be programed by the Arduino IDE which is a software installed on a desktop or laptop. The Arduino IDE can be downloaded from here.

                When you open the IDE it looks like this. When you first connected your Arduino board to your PC with the help of a USB cable you have to select your hardware in the IDE. For this select

Tools > port > Hardware name (Your hardware should appear  here).

Now your hardware is ready for programing.

                As you can see the program starts with two functions named void setup()and void loop(). In almost all Arduino programs these two functions are essential. The basic template of Arduino IDE is shown below

       void setup() {

//set up stuff to only run at the beginning 

}

    void loop() {

//which consist of the statements about the program

} 

We discuss all of these functions later.

                                            

CONDENSER MICROPHONE AMPLIFIER

           This circuit is basically a multi stage RC coupled amplifier. The main components required are following.

• CONDENSER MICROPHONE 
  
• 1K PRESET OR POT
  
• BC147 AND BC149 TRANSISTORS 
• RESISTORS 
• CAPACITORS 
• 6V POWER SUPPLY
• BREADBOARD  OR PCB
  

CIRCUIT DIAGRAM 

                    The circuit is a multistage amplifier capable of amplify the low power signal generated by the microphone. Transistor BC149 utilise current series feedback the first stage. The second stage comprising transistor BC147 is connected in the voltage shunt feedback configuration. These two stages provide sufficient gain to pick up even the slightest whisper.