HiLetgo 2004 20X4 LCD Display LCD Screen Serial with IIC I2C Adapter Yellow Green Color LCD for Arduino Raspberry Pi

As an I2C device this was a no brainer and didnt consume any pins on my Arduino since the I2C bus is shared with several other devices. Once you adjust the potentiometer for the brightness it is very nice to read. It needs a different library than its 16x2 cousin but that was a breeze to find and install.

I2C is the way to go to minimize the pin count used on your board. Love the contrast Black on Yellow display very bright and very easy to read, The Contrast control works great. Price point is about right for this product and Yes I will purchase more the next time I need more displays .

price very good deliver fast come assembled

Follow Up: I just received the 2nd screen that I ordered to replace the broken one. This one is defective as well. This time it is detected on the I2C bus 1/5th of the time if that, and when sending data to it it similarly only works a small percentage of the time. Most of the time is doesnt respond at all - just the white blocks on 2nd and 4th rows. I should mention that I2C sensors and an OLED screen on the same I2C bus (same pins, wires) work 100% of the time. Will not be buying screens from HiLetGo anymore. Go with another brand for a few dollars more. Did not work. I scanned all I2C addresses and it did not show up at all - tried different wires, different spots on breadboard, etc to no avail. I also tried sending data to the two addresses suggested by others - but nothing happened. All it would do when connected to power is show the backlight and two rows (row 2 and 4) of white blocks. Contract adjustment did not help.

I hooked this 20 x 4 line display up as my temperature monitor. Works great and in programming all you need to know is the lines you are displaying (4) and the max characters you display (20). I blew one with walking on my rug and zaping it with static discharge, now i get square characters.

I bought this display to use in a GPS clock that displays local time and date and UTC time and date. Here are my observations. 1. Its big! I should have read the specs more closely, but its much bigger than I expected. 2. The contrast is OK, but its nothing to write home about. 3. The viewing angle is very small. Once you get about 30-degrees off-axis, the contrast falls off rapidly. You have to be almost dead in front of the display to read it. 4. The default brightness of the backlight is very bright - too bright for me - harsh even. It lights up a room at night. I added a 330-ohm resistor to tone it down a bit. Otherwise, its a standard LCD display, and writing code for it is pretty simple. For what its worth, the hd44780.h display library is MUCH faster than other libraries (such as LiquidCrystal_I2C.h). I highly recommend it. I am undecided if I will use this display in my project. The viewing angle is just so small, and thats not great for a clock. A TFT display can be had for about the same price, and the viewing quality and versatility are much better. That being the case, I would not recommend this display.

Good product. Good seller.

It works as expected. Pretty easy to read once you adjust the contrast. Rated at 4 stars because it comes with zero documentation. They do seem to be pretty standard so I was able to get it working using an example for Arduino online.

I received the LCD display like a couple of months ago and its still working and is way better than the led display that comes with the elegoo Arduino kit. also I am a human and also um...I forgot what I was gonna say. OH YEAH to get the library for the display you just look for LiquidCrystal_I2C by Frank de Brabander and you should be good. Again goof luck, this is a good product.

It works nicely and seems to be good value for the low cost. I had to play around finding the right library file to get it to work-the one on Last Minute Engineers works fine, and they have a nice tutorial to help get it running.