Engineers Garage

  • Electronic Projects & Tutorials
    • Electronic Projects
      • Arduino Projects
      • AVR
      • Raspberry pi
      • ESP8266
      • BeagleBone
      • 8051 Microcontroller
      • ARM
      • PIC Microcontroller
      • STM32
    • Tutorials
      • Audio Electronics
      • Battery Management
      • Brainwave
      • Electric Vehicles
      • EMI/EMC/RFI
      • Hardware Filters
      • IoT tutorials
      • Power Tutorials
      • Python
      • Sensors
      • USB
      • VHDL
    • Circuit Design
    • Project Videos
    • Components
  • Articles
    • Tech Articles
    • Insight
    • Invention Stories
    • How to
    • What Is
  • News
    • Electronic Product News
    • Business News
    • Company/Start-up News
    • DIY Reviews
    • Guest Post
  • Forums
    • EDABoard.com
    • Electro-Tech-Online
    • EG Forum Archive
  • DigiKey Store
    • Cables, Wires
    • Connectors, Interconnect
    • Discrete
    • Electromechanical
    • Embedded Computers
    • Enclosures, Hardware, Office
    • Integrated Circuits (ICs)
    • Isolators
    • LED/Optoelectronics
    • Passive
    • Power, Circuit Protection
    • Programmers
    • RF, Wireless
    • Semiconductors
    • Sensors, Transducers
    • Test Products
    • Tools
  • Learn
    • eBooks/Tech Tips
    • Design Guides
    • Learning Center
    • Tech Toolboxes
    • Webinars & Digital Events
  • Resources
    • Digital Issues
    • EE Training Days
    • LEAP Awards
    • Podcasts
    • Webinars / Digital Events
    • White Papers
    • Engineering Diversity & Inclusion
    • DesignFast
  • Guest Post Guidelines
  • Advertise
  • Subscribe

How to take input from a particular pin of ATmega16- (Part 5/46)

By Ashutosh Bhatt February 4, 2011

For understanding the human needs a system must be able to take input from user. The devices which can be used to take input for a system are keypad, touch screen, etc. In the article LED blinking, the microcontroller drives the LED or in embedded language the microcontroller was set to give o/p, this article gives brief information of getting an input from user at a particular pin of microcontroller.
 

 

In order to take input from an external source on any of the pins of the AVR microcontroller, the pins need to be configured as input pin. This configuration informs the controller that the corresponding pins are used to take input. The following steps explain how to take input from a pin:
 

Block Diagram to take input on Atmega16 pin

Fig. 2: Block Diagram to take input on Atmega16 pin
 
Step1: Set the direction of PORT
To use a port as an input port first set the direction of port. DDRx (Data Direction) Register is used to set the direction of port.
DDRA=0x00;
In DDRA, ‘A’ shows the portA and 0x00 sets all the pins of port as input pins. (Writing 0 in DDR makes it input pin and writing 1 in DDR makes it output pin.
 
Step2: To take input form a port
Make a variable and use PINx instruction to get the input from a port
Value=PINA;
Where Value is a variable.
 
How to compare a pin?
To compare a pin, the instructions bit_is_set or bit_is_clear can be used. These instructions are define in avr/sfr_defs.h library. There is no need to include this library in code if avr/io.h has been included.
 

Project Source Code

###

// Program to take input from a particular pin in AVR Microcontroller (ATmega16)
#include<avr/io.h>
#include<util/delay.h>

int main (void)
{
unsigned int i=0;
DDRA=~_BV(PA0); // PA0 as input pin
PORTA=0x00;
DDRD=0xff;

while(1)
{
PORTD=0x01;
while(PORTD!=0)
{
if(bit_is_set(PINA,PA0)) //If PA0=1
{
_delay_ms(100);

if(bit_is_set(PINA,PA0)) //Check it again due to swithc debouncing
PORTD=(PORTD<<1); //Left shift value of PORTD by 1

}

}
}
}

###

 


Circuit Diagrams

Circuit-Diagram-of-How-to-take-input-from-particular-pin-of-ATmega16

Project Components

  • ATmega16
  • LED

Project Video


Filed Under: AVR
Tagged With: atmega16, avr, input, led, microcontroller
 

Next Article

← Previous Article
Next Article →

Questions related to this article?
👉Ask and discuss on EDAboard.com and Electro-Tech-Online.com forums.



Tell Us What You Think!! Cancel reply

You must be logged in to post a comment.

EE TECH TOOLBOX

“ee
Tech Toolbox: 5G Technology
This Tech Toolbox covers the basics of 5G technology plus a story about how engineers designed and built a prototype DSL router mostly from old cellphone parts. Download this first 5G/wired/wireless communications Tech Toolbox to learn more!

EE Learning Center

EE Learning Center
“engineers
EXPAND YOUR KNOWLEDGE AND STAY CONNECTED
Get the latest info on technologies, tools and strategies for EE professionals.

HAVE A QUESTION?

Have a technical question about an article or other engineering questions? Check out our engineering forums EDABoard.com and Electro-Tech-Online.com where you can get those questions asked and answered by your peers!


RSS EDABOARD.com Discussions

  • Thermal modelling of repetitive power pulse
  • Redundant XORs
  • No Output Voltage from Voltage Doubler Circuit in Ansys Nexxim (Harmonic Balance Simulation)
  • Discrete IrDA receiver circuit
  • ISL8117 buck converter blowing up

RSS Electro-Tech-Online.com Discussions

  • Help with finding unique wire lug(s)
  • Simple LED Analog Clock Idea
  • Kawai KDP 80 Electronic Piano Dead
  • Saga 1400sv vinyl cutter motherboard issue
  • using a RTC in SF basic

Featured – LoRa/LoRaWan Series

  • What is the LoRaWAN network and how does it work?
  • Understanding LoRa architecture: nodes, gateways, and servers
  • Revolutionizing RF: LoRa applications and advantages
  • How to build a LoRa gateway using Raspberry Pi
  • How LoRa enables long-range communication
  • How communication works between two LoRa end-node devices

Recent Articles

  • What is the LoRaWAN network and how does it work?
  • Understanding LoRa architecture: nodes, gateways, and servers
  • Revolutionizing RF: LoRa applications and advantages
  • How to build a LoRa gateway using Raspberry Pi
  • How LoRa enables long-range communication

EE ENGINEERING TRAINING DAYS

engineering

Submit a Guest Post

submit a guest post
Engineers Garage
  • Analog IC TIps
  • Connector Tips
  • Battery Power Tips
  • DesignFast
  • EDABoard Forums
  • EE World Online
  • Electro-Tech-Online Forums
  • EV Engineering
  • Microcontroller Tips
  • Power Electronic Tips
  • Sensor Tips
  • Test and Measurement Tips
  • 5G Technology World
  • Subscribe to our newsletter
  • About Us
  • Contact Us
  • Advertise

Copyright © 2025 WTWH Media LLC. All Rights Reserved. The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of WTWH Media
Privacy Policy

Search Engineers Garage

  • Electronic Projects & Tutorials
    • Electronic Projects
      • Arduino Projects
      • AVR
      • Raspberry pi
      • ESP8266
      • BeagleBone
      • 8051 Microcontroller
      • ARM
      • PIC Microcontroller
      • STM32
    • Tutorials
      • Audio Electronics
      • Battery Management
      • Brainwave
      • Electric Vehicles
      • EMI/EMC/RFI
      • Hardware Filters
      • IoT tutorials
      • Power Tutorials
      • Python
      • Sensors
      • USB
      • VHDL
    • Circuit Design
    • Project Videos
    • Components
  • Articles
    • Tech Articles
    • Insight
    • Invention Stories
    • How to
    • What Is
  • News
    • Electronic Product News
    • Business News
    • Company/Start-up News
    • DIY Reviews
    • Guest Post
  • Forums
    • EDABoard.com
    • Electro-Tech-Online
    • EG Forum Archive
  • DigiKey Store
    • Cables, Wires
    • Connectors, Interconnect
    • Discrete
    • Electromechanical
    • Embedded Computers
    • Enclosures, Hardware, Office
    • Integrated Circuits (ICs)
    • Isolators
    • LED/Optoelectronics
    • Passive
    • Power, Circuit Protection
    • Programmers
    • RF, Wireless
    • Semiconductors
    • Sensors, Transducers
    • Test Products
    • Tools
  • Learn
    • eBooks/Tech Tips
    • Design Guides
    • Learning Center
    • Tech Toolboxes
    • Webinars & Digital Events
  • Resources
    • Digital Issues
    • EE Training Days
    • LEAP Awards
    • Podcasts
    • Webinars / Digital Events
    • White Papers
    • Engineering Diversity & Inclusion
    • DesignFast
  • Guest Post Guidelines
  • Advertise
  • Subscribe