This module allows you to connect any type of LCD display compatible with the HITACHI HD44780 chip ( which is fitted to many LCDs ), whether they have 2 or 4 lines of 16 or 20 characters, or even more on an I²C bus. It is in fact a simple 8-bit parallel converter to an I²C serial bus which uses a PCF8574T chipfrom PHILIPS.
The LCD display is connected to the module in 4-bit mode, has a backlight control disconnectable via a jumper. It has of course a small potentiometer which allows to adjust the level of the contrast.
By default, the configuration of the address bits is 0100111 X , or $ 4E ( the X being the R / W read / write bit ), but it is possible to modify this via the 3 pads listed A0, A1 and A2 in adding a weld point. By proceeding in this way, one or more of these 3 pins is set low, which ultimately makes it possible to reprogram an address of your choice. On this version of the module, the 3 pads ( SJ1..SJ3 on the diagram ) that I left intact are located just below the contrast adjustment potentiometer.
Once again, I would like to point out that this module is not specially designed for Arduino, but remains fully compatible in general with any micro-controller-based system, whatever it is ...
I use it personally on a development platform mikroElektronika " Ready for PIC"In the development of a data logger found on the Internet, on the website of Paul FREYER , which is also very active on several forums .. .
I take this nod to thank him for sharing his knowledge and his original ideas.
He has developed a multitude of applications that deserve our attention. They sometimes require some adaptations depending precisely on the material we have at his disposal, but this is the process which remains interesting above all,
here is for example the type of display that the datalogger allows to obtain in I²C mode, with a 4x20 character display:
- 1 x 16-pin male connector for connecting an LCD display
- 1 x 4-pin male connector with the following markings: VCC / SCL / SDA / GND
I do not deliberately mention any library managing this LCD in I²C mode, quite simply because there are a lot of them on the Internet, and that it also and especially depends on your programming environment ( mikroElektronika, Arduino and many other ... )
I leave you the leisure to search a little on the web, it is not possible for me here to list them all ...
Dimensions : 42 x 20mm (W x D)
→ I bought this module here in November 2015 for 2.30 € ( free shipping ).