LOW POWER PIR
- http://dwmzone.com/blog/user-guide-for-dwm-pm-6-20ua-lowest-standby-current-1-8s-to-1hour-delay-time-mini-infrared-pir-module/
- http://dwmzone.com/blog/e931-96-ultra-low-power-pir-controller-integrated-circuit/
- http://dwmzone.com/blog/software-development-guide-for-e931-96-reading-and-writing-functions/