In this article I put a keyboard for activate and deactivate a alarms system with Arduino board and PIR sensor.
My schematic is:
and sketch is alarm_system_2a.ino !
My alarm work in next steps:
- after power on, alarm is OFF, blue led is on
- after you introduce the code (1234* or better #1234* because # clear buffer for old activity) system go to stand-by state, green led is blinking;
- after 20 seconds, system is in waitting (watching) mode, green led is permanent on;
- if PIR sensor detect movement, system begin to countdown, red led flash;
- if you indroduce code, system will be off (blue led in on)
- after 10 seconds (if you not enter the code) buzzer is on (led onboard is on), red led is permanet on
- after 10 seconds, system go to waitting mode, if is movement again, countdown and after buzzer is on, etc;
You can see 2 movies with states of this alarm system: