maalbalawi / timer_arduino

Countdown Timer: Range 1-99 minutes. Output: time (mm:ss) to seven segment display(TM1637) and Audio to Buzzer. Input: Push button to start. 10K Pot used for time select.

Table of contents

• Table of contents
• Overview
• Library
• Parts List
• Features

Overview

• Name: timer_arduino
• Title: Micro-controller Countdown Timer
• Description: Countdown Timer: Range 1-99 minutes. Output time (mm:ss) to seven segment display(TM1637) and Audio to Buzzer. Input: Push button to start. 10K Pot used for time select.
• Author: Gavin Lyons
• Note: Two alternative designs, two different ino files. One with Attiny85 IC the other with an arduino nano.

Library

• TM1637Display.h to drive the Tm1637 module Version 1.1.0 link

Parts List

The schematic drawn in eagle is in documents section.

You will need following parts.

Arduino based board with 4 digital pins and 1 analog pin. (In this case nano or Attiny85)

Resistor: 220ohms

tm1637 seven segment I2C module

one 10 k pot

one pushbutton

One on/off SPST switches

One piezo buzzer

oNE 100nF capacitor

tm1637 7-segment I2C module.

Features

The user selects the countdown time (1-99 minutes) with the pot then starts with the pushbutton. Time remaining is displayed on seven segment display. When finished the buzzer is activated and done displayed on 7-seg. Two alternative designs, two different ino files and schematics. Design one uses the nano, design two the attiny85.

Design number one : file: timer_arduino.ino based on arduino nano.

Design number two : file: timer_attiny85_arduino.ino based on attiny85. The current consumption of this circuit is 9mA in countdown state and 11mA in alarm state. The brightness of display is set to a low setting in the program.