LCD (20x4 made in China)

[pepijn]

This week i received one of my latest Chinese investments.
A Blue 20x4 LCD display with I2C interface.

Hooked it up to my (test) Raspberry i did not want to blow my production Banana Pro.
Some Pyhon coding, mostly cut and paste.

The result:
https://vimeo.com/127908552

[tlpeter]

That looks nice.

[rtna]

Can you write a how-to?

Is it this one?

http://nl.aliexpress.com/item/Free-ship ... 17726.html

[pepijn]

Is it this one?

http://nl.aliexpress.com/item/Free-ship ... 17726.html

That's the type of display i used. You can find them on EBay for arround 6 euro's

[ThinkPad]

Looking good! That's nice to combine with this housing: https://www.sossolutions.nl/raspberry-p ... dinrail-2b (DIN-rail) so you can fit it into your meter cabinet.

Maybe you can share your code here ?

[D'rMorris]

Posting the code would be great, with this I'm gonna build my own security system

[u01pei]

Sharing the code Would be great!

[pepijn]

Yes I will share the code, but need to clean it up a bit.

[u01pei]

Great! Thanks Pepijn.... Goed bezig!

[pepijn]

This is a nice tutorial (in Dutch) on how-to connect the screen.
http://www.gejanssen.com/howto/i2c_disp ... index.html

I also attached my Python scripts.

[D'rMorris]

Thanks Pepijn!

My next project .

[schmm]

nice work!

I will try this!!

[lrybak]

Nice work pepijn. Have you tried to operate domoticz switches via ex rotary encoder?
It would be very nice fature to turn on/off switches directly w/o turning computer or smartphone

[mariusvanderwerff]

Hi there,

I'm a noob in this, can you tell me how to install the scripts on my Pi?

Regards, Marius

[u01pei]

Hello Marius,
Since you're Dutch, as are most of the people here, read this:
http://www.gejanssen.com/howto/i2c_disp ... index.html

[mariusvanderwerff]

Hi u01pei,

thnx for the reply,

did everything but got only a nice blue screen,

from lcd_display import lcd

my_lcd = lcd()
my_lcd.display_string("Hello World", 1)
my_lcd.display_string("YwRobot LCM1602 IIC V1 display", 2)
my_lcd.display_string("aan de Raspberry Pi", 3)
my_lcd.display_string("via gejanssen.com", 4)

This didn't work also.. any idea's ?

[u01pei]

Perhaps your address is wrong? try this:
enter this command on your pi:
i2cdetect -y 1
if it doesn't work, enter:
i2cdetect -y 0

Check the number in the table, this is your address. If there are more devices on your I2c bus, there will be several addresses visible. To be sure, unplug all other devices and the address left will be the LCD (or try them all)

To use the correct address in the python script:
open the script named lcd_display.py
on line five you will see 0x27
change the 27 into whatever you found in the I2c table. (leave the 0x as is).

Good luck

[mariusvanderwerff]

Hi u01pei,

the address is correct:
pi@raspberrypi ~/domoticz/scripts/lcd $ sudo i2cdetect -y 1
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- 27 -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --

import i2c_lib
from time import sleep

# LCD Address
ADDRESS = 0x27

Checked that already....

[u01pei]

Sorry Marius,

I am a noob myself, so I don't have any clue on what you could do next.

[lrybak]

Marius,
Double check wiring and try another simple "hello world" program to be sure that everything is ok