more readme

README.md

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 Lua code, scripts, and firmware for my smart light project.
+
+## How to use
+You can flash this to your esp8266 (with nodemcu on it), change the pin numbers correspondingly, and it should work.
+
+It has a relay attached to it that switches a lot on/off depending on the voltage, as well as a temperature sensor connected to the ADC (analog-digital converter) pin, which is used to handle motion detection using a sonar sensor. You can modify the code according to whatever hardware you have.
+
+The main useful thing here is the code for getting reliable sonar readings.
+
+Hardware used:
+
+* https://www.adafruit.com/product/3942
+* https://learn.adafruit.com/adafruit-power-relay-featherwing
+* https://www.nodemcu.com/index_en.html
+* https://www.adafruit.com/product/165