AZDelivery Compatible with HD44780 1602 16x2 Serial LCD Black Character Green Backlight Display Board IIC PCF8574T I2C Adapter Converter Bundle Compatible with Arduino Including E-Book! (Pack of 5)

I tried this connected to a Raspberry Pi CM4 & I/O Board and it wouldn't work off 3.3V (backlight was OK, character display gave random characters so not so OK). It worked fine off 5V but to ensure Pi voltage tolerance I de-soldered the 2 4K7 I2C pull-up resistors from the backpack/interface board i.e. those connected to the PCF8574 pins 14 & 15, allowing only the Pi 3.3V pull-ups to do their job. The voltage level to the PCF8574 might now be technically slightly too low but it seems to work OK.

Works well once set up properly. I'd recommend downloading and installing Bill Perry's HD44780 library, which has an extensive range of examples and debug scripts. If you're using it with the serial backpack you need hd4480_12Cexp.It says that it includes an eBook, but there's little indication of where to find that. If you go to the EZDelivery web site, you will find a list of eBooks. But if you go through the full process of finding the right book, ordering, "paying" (there's no charge) and downloading it, you'll end up with an image file called "eBook is under construction.png". Instead, you need to download the file "LCD 20x4_FC-113 - ENG.pdf" which is for the 4-line display, but the connections are the same.The product includes an I2C serial "backpack". This needs to be soldered onto the display in order to use the simpler 4-wire serial interface. You can use the display without it, but you'll need a lot more wiring.One thing that caught me out is the little potentiometer on the back. This is "to adjust contrast", but until I turned it I didn't see *anything* on the display. This made me think that either my connections or my software were wrong, until I eventually tried turning it and the display popped into life. This was the same on both the displays I bought, so isn't a one-off glitch.

If I am not in a hurry for something, I generally order this sort of stuff from Aliexpress because it is generally much cheaper - but - you do have to be prepared to wait (sometimes months) for delivery. In this case, these were just as cheap and I needed one quickly, so I took a chance. I was a bit sceptible about the quality given the price but I have had no issues with any other items. I tested them all on arrival and they all work fine. Well worth the gamble: same price, no wait.

paid disproportionately to get it delivered quicker but missed them by7 minutes. Meaning this particular delivery people go store it in some dungeon til you get to it ( between 7 and 9 am ).The product (cheap enough) works perfectly - thank you - but Im giving 4 stars for your delivery service people.

Product description said they came with a free eBook. This was important to me because finding information on electronic components on the internet can be difficult due to different versions etc.I have received a number of emails from AZ-Delivery (all in German) with links to the document but it always says your eBook is under construction.Other than that they seem to work OK and were delivered quickly.Update as at 30th April 2020 - the eBook link they sent me still says "Your eBook is being prepared"

Used this display with I2C to create a timekeeping digital WIFI clock used along with the Raspberry Pi Zero WH and a DHT11 temperature sensor module. Displays a greeting message, temperature, humidity and time all encased in a waterproof box . Adding an additional potentiometer can adjust display brightness.Also able to SSH into the PI to change the code.

There's little to say about this display, as it's a more or less standard item.The only unusual thing it that the I2C module is supplied separately, not preinstalled. I quite like this, because I can choose to use I2C or nybble / byte parallel mode. Might not be so good if you don't have a soldering iron!

I am the world's worst with hardware. wiring things up is a pain to me but these little !2c beauties are so easy to wire up that even I can do it quickly and then get on with the fun bits.