Hi everyone! I need a light to be turned on for a certain amount of hours, and then off for another amount of hours, how can I achieve this?
Thank you.
Hello and welcome!
You can use a square-wave node to cycle on and off phases. Use time-to-duty to set up its DUTY value. In its turn, Ton will define light “on” time (in seconds) and Toff defines off-time. One hour is 3600 seconds 
If you still have questions, feel free to ask.
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Thank you for the reply. Yes I have some other questions:
- Because I am using a lot of digital pins I don’t have enough space for a classic lcd so I used a i2c module, if I put the wrong addr is it going to damage the i2c module?
- I want to make a menu in the lcd that allows (when a button is pressed) to switch between views with different data, how do I do that?
- If I use a 16x3 module how can I have access to the 3rd line?
Thank you so much for helping me and sorry for all of these questions but I know only the basics of electronics.
No, absolutely not. The worst thing going to happen is you will not see the text.
One possible way is to have if-else-string nodes right before the LCD node. Another solution is to have multiple LCD nodes that refer to the same display, but have gate-string nodes before each one and keep only a single gate pair open.
Do they exist? Thats not directly possible with already existing nodes, but you can copy implementation of the 16Ă—2 and make small adjustments (add an input and few lines in C++) to make your own text-lcd-16x3-i2c node.
You can try this:
Add library --> dox/lcd-i2c
I found a 16x3 Display with SPLC780D Controller. This could be compatible to standard HD44780 controller. No guarantee that it will work. I am not a programmer. This is just a modification of the existing nodes.
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Thank you for the detailed answers.
Is it possible to have access to the serial monitor?
Sure. Use console-log node and upload with “Debug after upload” checkmark set.
How do I convert a analog signal in a string?
Simply link your number output (from an analog-input) to a string input (like L1 on text-lcd or if-else-string) and magick will happen. If you’re not satisfied with the magick, use the format-number node.
Hi…if you have metal halide lights a cheap timer will fail at some point as the ballast draws a lot of current for a split second at start up. a heavy duty timer may be a consideration. Otherwise go for a cheap one.