Door Indicator - When the garage door is closed a green LED is on solid. When the garage door is opened a red LED is blinking. This feature will allow you to check the door state without going to the garage depending on where you put your garage monitor.
Door Alarm - If the garage door is left open longer than 5 minutes, it will sound three 1 second beeps. It will repeat every 3 minutes thereafter until the door is closed or the sound is disabled.
Door Chime - If enabled, this feature will sound two or three 100ms beeps when the garage door changes state. If the door is closed, it will sound two 100ms beeps, and if the door is opened it will sound three 100ms beeps. To toggle this feature (it is remembered in EEPROM), hold the beep disable button down while powering on. Both green and red LED will be on solid and the yellow LED will indicate if this feature is enabled or not. Tap the beep disable button to toggle it. Hold the beep disable button to exit or power cycle the unit to exit.
Beep Disable - This feature allows the user to disable all sound from the unit for one to eight hours. If you want to work in the garage and plan on leaving the door open for a couple of hours, you can use the beep disable to prevent any alarms from coming from the unit. Without this feature, someone likely would have unplugged the unit and then possibly forgotten they unplugged it. The nice thing about this feature is that within one to eight hours, the unit is back to normal.
This project could also be used for something instead of a garage door too; anything that has two states and you want an indicator of which state.
If you discover any issues or something needs correcting, let me know.
I have two extra PCB's right now (1.00), if someone in the US wants one for $8 shipped just drop me a PM.