Sketch for a user settable timer controlling a relay output. The hardware system for this code is described in the Arduino++ blog
- Arduino Uno/Nano/Mini/etc
- 7 segment 4 Digit LED display
- Rotary encoder with built in selection switch
- Relay output or relay module
- Arduino manages the LED display
- Rotary encoder allows setting the required timer value
- Rotary encoder switch used to start the timer
- Timer can be paused with a press of switch. Second press resumes and long press ends the timer.
- While timer is active (running or paused) the relay output is switched on.