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