GeeekPi IIC I2C TWI Serial LCD 2004 20x4 Display Module with I2C Interface Adapter Blue Backlight for Raspberry Pi Arduino STM32 DIY Maker Project BPI Tinker Board Electrical IoT Internet of Things

A good 4x20 LCD with attached I2C controller. Although the picture implies that the controller can be removed, it cannot without unsoldering all the connections to the display itself. Functionally fine, but be aware that I2C LCD controllers are "slow" compared to the standard, multi connection (many wires) method. One may want to try various libraries if refresh speed is an issue.

Arrive on time and worked right out of the box. This is my second 2004-LCD I2C, from Geeekpi and it works well.

I originally gave this a bad review because it would not work, but it turned out that the references for sample code were for a different Arduino. Once I realized those instructions were old, outdated, etc., I found a page with the correct instructions for my board and it works perfectly.There are two things to look at - the first is the hardware, it just works, four lines, 20 columns, bright and readable. The other is the interface software that your code will use. Like most things these days, the documentation is spotty, many times it is only the ramblings of somebody writing click bait.Once you have the library installed (and it most likely will be installed with a general update if not already there) and looked at the provided example, it is insanely easy to code. There are nuances with the library and hardware that need to be learned, and some techniques, but for 10 bucks or so, it is a great buy.

Overall a pretty standard LCD screen and works well for my applications. Beware though, the way they show this connecting directly to a Raspberry Pi is false. For an Arduino, connect directly to the screen is acceptable, but for the Pi it isn’t. This screen, and essentially all like it, work with 5V logic. Arduinos natively use 5V logic, which is OK. The Raspberry Pi, on the other hand, has 3.3V logic on the GPIO pins. DO NOT PLUG THIS DIRECTLY INTO YOUR PI! You risk damaging the Pi. You need a bidirectional level shifter between the Pi and the device to bring the voltage down from 5V logic on the LCD side to 3.3V on the Pi side! Other than that, this thing is great!

I had to buy this for a college project, and the screen worked. At first, the screen was too bright and reading the text was kind of tough, but using a resistor made it crystal clear.

Great, basic, easy to use for Arduino projects. Lots of space on the display and I2C makes for an easy connection.

Easy to use display with my Arduino UNO. Just activate the appropriate LCD library with in the Arduino IDE and add the correct code and I2C address of the GENIO expander on the display (0x27) for the one I received.It might have been a little more fun and challenging to figure out how to write the code to control the IO expander to the display, but using the Arduino library makes it easier and quicker to implement into your project.

The LCD 1602 2004 are like the Kleenex of simple displays, with the later upgrade from parallel to IC22 wire. These work great, and the led can be PWM'ed to control brightness with a a.nano or a.unolove it