Wednesday, 7 February 2018

Arduino and processing based GUI person counter

In this post, we will make arduino and processing based GUI person counter. For person counter, we are using infrared sensor (IR). It's output is digital and is fed to pin number 7 of arduino.

The connections are as follows:
Connection of arduino with proximity sensor

Interfacing HC-05 with Atmega8

In this post, we will interface bluetooth module (HC-05) with atmega8. Atmega8 is a 28-pin IC and it has three ports viz., PORTB, PORTC and PORTD and it has total 23 gpio pins. It has internal rc oscillator, that is user selectable from  1, 2, 4 or 8 MHz.

We are using 8 Mhz internal rc oscillator.

Compiler Used: GCC

Connection is as follows:

Atmega8                                     BT module
RX            ============>     TX
TX            ============>     RX
GND         ============>     GND
VCC         ============>     VCC

We are using uart at baud rate 9600. Make sure that BT module and atmega8 both have same baud rate.

Saturday, 12 August 2017

Getting Started with NodeMCU

Hello Friends,

Today we will write first program for NodeMCU3 that is led blinking. NodeMCU3 has esp12e and ch340 (USB-TTL) on-board. It can be connected to PC/ Laptop via USB mini(type B) data cable.

Let's get started.

All we need is NodeMCU3 and arduino IDE.
LED and resistor

Tuesday, 1 August 2017

Step by step installation guide for ch340 USB-UART converter

Hello Friends,

In this tutorial, we will cover how to install ch340 driver for different versions of windows.
CH340 is USB-UART converter and is used for serial communication with PC/ laptop with external device e.g. GSM module, GPS module, arduino pro, etc.

Things required:


Monday, 3 July 2017

4-Digit Seven Segment TM1637 Display interfacing with arduino

Hello Arduino Lovers,

In this post, I am going to interface 4-digit seven segment display with arduino. It's TM1637 based display and it just requires 4-pins. And it's better than conventional 4-digid SSD since that requires 12 (8+4) output pins. So, it saves our pin. As MCU have limited I/Os it's very useful.

The pins are as follows:


It's 2-wire serial communication and it's different from I2C communication.

Sunday, 11 June 2017

Generating a delay of 1s using timer in atmega8

Hello Friends,

In this tutorial, we will learn how to generate a delay of 1second using timer0 in atmega8.

We are writing the code in Avr studio 4.

Timer 0 is a 8-bit timer means we can feed any value from 0 (0x00) to 255 (0xff)

Timing Diagram
In this example, we are using prescaler of value8. Prescaler divides the base frequency (provided by crystal or internal rc oscillator).

Machine Cycle = 1/Fosc      (Fosc is 8 MHz)

M.C = 1/8 us or 0.125 us

Delay = (256-x) * 0.125 * Pre scaler  (Pre scaler = 8)

Friday, 24 March 2017

Matlab with Arduino - Part 1

In this post, we are going to install arduino library in matlab.
There are two options available:
Online and Offline support package for matlab. We are using offline method for installation of arduino library.

  • Matlab 
  • Matlab account (for downloading support package)
  • Arduino IDE
  • Arduino UNO board
First of all, download the support package zip file from:

Thursday, 16 March 2017

Temperature based fan speed control using arduino uno and lm35

In this post, we will make a temperature based fan control using arduino and lm35. LM35 is temperature sensor, whose output is analog (linear). Arduino uno has six channle of adc (A0-A5)
and adc is of 10-bit

Stuff required:
  • Arduino UNO
  • LM35
  • LCD 16*2
  • POT 10k
  • Motor driver (L293D)
  • DC motor