Character LCD I2c Adapter (I2c Connection Example)

by xxreef in Circuits > Electronics

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Character LCD I2c Adapter (I2c Connection Example)

SchemaLCD_i2c_bb.png
Character LCD I2c Adapter (Standard library)

I'm doing a connection schema for a character display i2c adapter.

Check the updates on my site.

Now I add olso a wiring connection schema to use original library not my forked.

LiquidCrystal Arduino library for the character LCD displays, forked project for create a personal schema to learn pcf8574.

In the github project you can find schema, photo and library code.

Here a video of milled PCB derived from Fritzing breadboard schema.

Part for Original Library

s-l1600[1].jpg

You can find the component for the original library (not my forked) from eBay.

Now here you can find the same connection schema that have same behavior.

Wiring Diagram: Back Light

NPN.PNG

As you can see in the wiring diagram I connect to P7 an NPN (2N2222) transistor to enable/disable backlight.

Wiring Diagram: Address

address.PNG
address.PNG

I set the address all low (you can connect It as you need, in the datasheet you can find all configuration).

I find very useful sketch that search all i2c component attached, use this to check address.

Wire Diagram: Trimmer

trimmerContrast.PNG

To select correct contrast you need to add a 10k trimmer.

Wiring Diagram: Transfer Data

ComunicationWire.PNG

Blue and yellow wire is to send data to device, I don't connect the device as original library so I must fork the lib and add some change.

Change to the Original Lib

change01.PNG
change02.PNG
change03.PNG
change04.PNG

As you can see in the image I shift some bit (right to left), and on right bit I put fixed declaration of Enable, RW, Register Select, and Back light pin.

If you want you can reconvert the schema to the original. If I find some time I'm going to do It for you (and test It) so you can use original library.

Original Lib and Connection Schema

breadbordStandardConnection.jpg
SchemaLCD_i2c_standard_bb.png
SchemaLCD_i2c_standardv02_pcb.png

I recreate connection schema of original library, so you can use standard library with this.

Wire Diagram: SDA SCL

SDASCL.PNG

Banded wire is the SDA SCL pin of my arduino.

Wire Diagram

SchemaLCD_i2c_bb[1].png
SchemaLCD_i2c_standard_bb.png
breadbordStandardConnection2.jpg

As you can see the wiring diagram is quite simple, than I try to create It on prototype board of the schema.

Prototype Board

preforatedUp.jpg
preforatedDown.jpg
preforatedlcd.jpg

It's not so beatiful but It's work.

Milling PCB

myRouter.jpg
SchemaLCD_i2c_cat_pcb.png
pcf8574_LCD_Adapter01.jpg
pcf8574_LCD_Adapter02.jpg
Character LCD I2c Adapter (Milled PCB)
pcf8574_LCD_Adapter03.jpg

From the schema I create a PCB and I try to mill PCB with my router (I'm starting a guide how to mill PCB).

Thanks