Practice Exercise: combining sensors and inputs.

In this section, I used push-button, photo resistance, and LED. The push-button is an overall switch and all the actions will happen only when the button is pushed. When the button state is low, the LED will dim according to photocell readings. But if the light levels are below 600, the LED turns off.

This is design for the following scenario: You want to read but you don't want to read with the lighting which is too strong and bad for your eye. The dimming is like the screen lighting level. The LED will adjust the dimming and when the ambient lighting is no longer suitable for reading, the LED will turn off. And there is an overall switch to control the dimming system.