Joy-it RB-LCD-20x4 User manual

www.joy-it.net
Pascalstr. 8 47506 Neukirchen-Vluyn
LCD DISPLAY 20X4
with Buttons
1. GENERAL INFORMATION
Dear customer,
Thank you for purchasing our product. In the following, we will show you
which things should be noted during the use.
Should you encounter any unexpected problems, do not hesitate to
contact us.
This manual is designed for version 2 of this display (PCF8574).

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2. CONNECTING THE DISPLAY
Put the display on the pin header that way, that the display is right above
your Raspberry Pi. As soon as the Raspbbery Pi is connected to a power
supply, the backgroundlight of the display will light up.
3. INSTALLATION OF THE SYSTEM
If your Raspberry Pi has the latest Raspbian soware, you can skip this
step. Otherwise, please follow the instructions.
Install card the latest Raspbian system image on your SD. You can
download it here.
With an appropriate program (e.g. Etcher), you can transfer the image
onto the SD card. Aer a successful transfer, the SD card can be put into
the Raspberry Pi and the system can start.

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4. USE AND CODE EXAMPLE - VERSION 2
To use the display completely, you must install first two libraries for the
display. First, you need the Python GPIO library from Adafruit which is
published under the MIT license. You install this library with the following
commands:
You can leave the subfolder with the following command:
cd ..
The second library is the Python CharLCD library from Adafruit which is
again published under the MIT license. You can install it like this:
git clone https://github.com/adafruit/Adafruit_Python_CharLCD
cd Adafruit_Python_CharLCD/
sudo python3 setup.py install
You leave the folder again with:
cd ..
Before the use of the display, you have to enable I2C. Therefore, enter the
following command to open the Raspberry Pi configuration settings:
sudo raspi-config
Select the option Interfacing Options and confirm with Enter:
git clone https://github.com/adafruit/Adafruit_Python_GPIO
cd Adafruit_Python_GPIO
sudo python3 setup.py install

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Pascalstr. 8 47506 Neukirchen-Vluyn
Aer that, select the option I2C :
The next message has to be confirmed with Yes and aer that, you can
leave the settings with Finish . I2C is now succesfully activated and you
can use now the display.
It could be necessary that you have to adjust the contrast manually
before you can see the output of the display.
Adjust the contrast therefore, that you can rotate the marked
potentiometer with a small screwdriver, like it is shown in the picture
below.

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Pascalstr. 8 47506 Neukirchen-Vluyn
To use the display completely, you can download the example code
here or you can create yourself a file and copy the following code into
that file.
To create a new file, you use the following command:
sudo nano lcd20x4.py
from Adafruit_CharLCD import Adafruit_CharLCD
import Adafruit_GPIO.PCF8574 as PCF
import RPi.GPIO as GPIO
LCD = PCF.PCF8574(address=0x27)
LCD.setup(5,0)
LCD.output(5,0)
# Declares which PCF pin is connected to which LCD pin
lcd_rs = 4# RegisterSelect pin is connected to GPIO4
lcd_en = 7# Enable pin is connected to GPIO7
d4,d5,d6,d7 = 0,1,2,3 # Data pins 4,5,6,7 is connected to GPIO 0,1,2,3
cols,lines = 20,4 # Number of columns and rows of the display
# Declares the pins of the Raspberry Pi to the buttons
SW1 = 4 #GPIO 4
SW2 = 16 #GPIO 16
SW3 = 10 #GPIO 10
SW4 = 9 #GPIO 9
GPIO.setmode(GPIO.BCM)
GPIO.setup(SW1, GPIO.IN, pull_up_down = GPIO.PUD_UP)
GPIO.setup(SW2, GPIO.IN, pull_up_down = GPIO.PUD_UP)
GPIO.setup(SW3, GPIO.IN, pull_up_down = GPIO.PUD_UP)
GPIO.setup(SW4, GPIO.IN, pull_up_down = GPIO.PUD_UP)
# Initializes the LCD
lcd = Adafruit_CharLCD(lcd_rs, lcd_en, d4, d5, d6, d7,cols, lines, gpio=LCD)
lcd.clear()
lcd.message('xx RB-LCDV2 Test xx\n 1234567890\n abcdefgh \n 0987654321')
# Watch the buttons:
try:
while True:
if GPIO.input(SW1) == GPIO.LOW:
lcd.clear()
lcd.message ("Button 1 pressed!")
if GPIO.input(SW2) == GPIO.LOW:
lcd.clear()
lcd.message ("Button 2 pressed!")
if GPIO.input(SW3) == GPIO.LOW:
lcd.clear()
lcd.message ("Button 3 pressed!")
if GPIO.input(SW4) == GPIO.LOW:
lcd.clear()
lcd.message ("Button 4 pressed!")
except KeyboardInterrupt:
lcd.clear()
GPIO.cleanup()

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Pascalstr. 8 47506 Neukirchen-Vluyn
PR
5. OTHER INFORMATION
Our Information and Take-back Obligations according to
the Electrical and Electronic Equipment Act (ElektroG)
Symbol on Electrial and Electronic Products:
This crossed-out bin means that electrical and electronic products do not
belong into the household waste. You must hand over your oldappliance
to a registration place. Before you can hand over the old appliance, you
must remove used batteries and replacement batteries which are not en-
closed by the device.
Return Options:
As the end user, you can hand over your old appliance (which has
essentially the same functions as the new one bought with us) free of
charge for disposal with the purchase of a new device.
Small devices, which do not have outer dimensions bigger than 25 cm
can be handed in for disposal independently of the
purchase of a new product in normal household quantities.
1. Possibility of return at our company location during our opening hours
SIMAC Electronics GmbH, Pascalstr. 8, D-47506 Neukirchen-Vluyn
2. Possibility of return nearby
We will send you a parcel stamp with which you can send us your old
appliance free of charge. For this possibility, please contact us via e-mail
at [e-mail] or via telephone.
Information about Package:
Please package your old appliance safe for transport. Should you not
have suitable packaging material or you do not want to use your own
material, you can contact us and we will send you an appropriate
package.
6. SUPPORT
If any questions remained open or problems may arise aer your
purchase,we are available by email, telephone and ticket
support system to answer these.
Email: [e-mail]
Ticket-system: http://support.joy-it.net
Telephone: [phone] – 66 (10 - 17 o'clock)
For further information visit our website:
www.joy-it.net
Published: 30.03.2020
www.joy-it.net
SIMAC Electronics GmbH
Pascalstr. 8 47506 Neukirchen-Vluyn
The file can be saved with the key combination CTRL + O and you can
leave the editor with CTRL + X.
Aer that, you can enter the following command:
sudo python3 lcd20x4.py