GPIO Pins Layout In ESP8266 Motor Shield

@J-M-L I was trying my hands on LCD. But it is not working :frowning:

I am using a LCD with an I2C module. I have made the proper connections for the 04 pins of the I2C module with the arduino. But nothing shows up on the screen after running the example of Arduino-Liquid-Crystal-I2C-Library-Master

#include <Wire.h> 
#include <LiquidCrystal_I2C.h>

// Set the LCD address to 0x27 for a 16 chars and 2 line display
LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup()
	// initialize the LCD

	// Turn on the blacklight and print a message.
	lcd.print("Hello, world!");

void loop()
	// Do nothing here...

So I want to ask is it necessary to solder the I2C module pins to the LCD ?

Also, I want to know that when we plug the LCD (along with I2C module) to arduino, does the Backlight of LCD glows by itself (even befire uploading any sktech) ? Because this is happening with me. Only the backlight is constantly glowing up and even after uploading the sketch nothing shows up on the LCD

Please suggest me a way :slight_smile:

don't post images of text... post your code using code tags...

(read How to get the best out of this forum and modify your post accordingly)

Done sir :slight_smile:


--- yes the I2C backpack must be soldered to the LCD module. Then you can use DuPont cables between your Arduino and the I2C backpack

Okay. But why they are not working without soldering?

because you need a good connection to not loose data or get noise

You need also to verify that 0x27 is your I2C address. LCD might be at different addresses

Nope. I confirmed the address of the LCD. That is why it's more weird that I am able to extract the I2C address of the LCD through the code.

But the LCD is not showing anything after running the program!

solder the backpack to the LCD. Then we can discuss :wink:

Okay :grin:
By the way is there a 16*2 LCD with an I2C module soldered ?

zillions !
eBay, amazon, aliexpress etc... they all have some I'm sure
just verify that it's already soldered...
(you might as well buy a soldering iron and do the job yourself if you plan to keep playing with Arduinos)

Can you please provide the amazon links for the soldered ones. I am not able to find those

usually if on the picture they don't show the I2C module separately and do not mention you have to solder it, then it's likely already mounted.

Depends on where you live, this one in France for example seems to be already soldered

you can always raise a question to the seller to be sure.