rpi_talktimer

LED display to indicate time elapsed during a presentation, with a push button to start and stop the sequence. Under the default settings:

• Green LED turns on for 10 minutes
• Yellow LED turns on after 10-12 minutes
• Red LED turns on after 12-14 minutes
• Red LED blinks after 14-15 minutes

To start, run the talk_timer.py Python script, e.g. on the command line python talk_timer.py

Hardware setup

LEDs are connected to GPIO pins and ground with an inline resistor

• Green LED is connected to pin 11 (GPIO 17)
• Yellow LED is connected to pin 13 (GPIO 27)
• Red LED is connected to pin 15 (GPIO 22)

A push button is connected to 3v3 power and pin 10 (GPIO 15) with an inline pull-down resistor.

Optional setup

To run the script automatically at startup:

Make sure the path to this this directory is correct in launcher.sh. By default it is located at /home/pi/Desktop/rpi_talktimer

Make launcher.sh executable with the command

chmod 755 launcher.sh

Edit your crontab by typing

sudo crontab -e

Enter the line (making sure to edit the path to launcher.sh if necessary

@reboot sh /home/pi/Desktop/rpi_talktimer/launcher.sh