xyb / lcd2usb

LCD2USB's Python Library

LCD2USB's Python Library

home: http://github.com/xyb/lcd2usb

PyPI: http://pypi.python.org/pypi/lcd2usb

Introduce

The LCD2USB's Python Library is a Pure-python wrapper for LCD2USB which provide a simple way to control your LCD2USB display device. LCD2USB is a open source/open hardware project to connect HD44780 based text LCD displays to various PCs via USB.

Usage

Connect a lcd2usb device is easy:

>>> from lcd2usb import LCD
>>> lcd = LCD()
>>> lcd.info()
Found LCD2USB device on bus 004 device 004.

Get lcd2usb firmware version:

>>> lcd.version
(1, 9)

Write something on the screen:

>>> lcd.write('Hello, LCD2USB!')

Clean screen and wirte some on the 2nd row:

>>> lcd.clear()
>>> lcd.goto(0, 1)
>>> lcd.write('Flying with PYTHON')

Or simpler:

>>> lcd.write('Flying with PYTHON', 0, 1)

Define a custom smile symbol and display it on the center of first row (on a 4x20 display):

>>> from lcd2usb import SMILE_SYMBOL
>>> lcd.define_char(0, SMILE_SYMBOL)
>>> lcd.write('\0', 9, 0)

That it!

If you need a quickly running test for your device, use this:

python -m lcd2usb

Requirements

• Python 3 required
• ctypes (included in Python)
• libusb-1.0
• python-libusb1

Installation

Installation is done just as for any other Python library. Using the pip or easy_install command from setuptools is the easiest:

pip install lcd2usb

Or:

easy_install install lcd2usb

lcd2usb's Issues

在windows环境下from usb2lcd import LCD时报错

exceptions.WindowsError
[Error 126]
开发环境使用的python2.7
不知是否我哪里操作不到位？
已经安装了
lcd2usb 1.2
libusb 1.0.22b4
libusb1 1.7

big characters

Hi,
is there any way to show big characters in the lcd? and different symbols? Something like this:

Or this one:

And for write symbols like this?:

Thank you very much for your support!!

Port to Python 3

Do you plan to port this module to Python 3?

Thanks!

script to show info in lcd

Hi,
I´m using your SW combined with RPI-Monitor to read the data from a sensor and place it in my lcd.
I´ve bought this lcd http://www.lcdmodkit.com/lcd/U204FR-A2.html which is compatible with lcd2usb.

The script that I´m using is this:

import httplib, time, os, sys, json
from lcd2usb import LCD
lcd = LCD()

# class Process dedicated to process data get from Client
# and send information to LCD and console
class Process:
  # Process constructor
  def run(self, jsonString):
    # Parse data as json
    data = json.loads( jsonString )
    # Try to get data from json or return default value
    try:
      rpi_temperature = data['living_room_temp']
    except:
      rpi_temperature = "--.---"
    try:
      rpi_humidity = data['humidity']
    except:
      rpi_humidity = "--.--"
    # Construct string to be displayed on screens
    temperature= "Temperatura: %s C" % rpi_temperature
    humidity= "Humedad:     %s %%" % rpi_humidity
    lcd.clear()
    lcd.write('Sensor RPi-Monitor', 0, 0)
    lcd.write('temperature', 0, 2)
    lcd.write('humidity', 0, 3)
    # Also print string in console
    os.system("clear")
    print " RPi-Monitor "
    print
    print temperature
    print humidity
    print
    time.sleep(1)

# Class client design to work as web client and get information 
# from RPi-Monitor embedded web server
class Client:
  # Client constructor
  def __init__(self):
    # Create a Process object
    self.process = Process()

  def run(self):
    # Infinite loop
    while True:
     try:
       # Initiate a connection to RPi-Monitor embedded server
       connection = httplib.HTTPConnection("localhost", 8888)
       # Get the file dynamic.json
       connection.request("GET","/dynamic.json")
       # Get the server response
       response = connection.getresponse()
       if ( response.status == 200 ):
         # If response is OK, read data
         data = response.read()
         # Run process object on extracted data
         self.process.run(data)
       # Close the connection to RPi-Monitor embedded server
       connection.close()
     finally:
       # Wait 5 secondes before restarting the loop
       time.sleep(5)

# Main function
def main():
  try:
    # Create a Client object
    client = Client()
    # Run it
    client.run()
  except KeyboardInterrupt:
    # if Ctrl+C has been pressed
    # turn off the lcd backlight
    lcd.backlight(0); 
    # exit from the program 
    sys.exit(0)

# Execute main if the script is directly called
if __name__ == "__main__":
    main()

I can check that the part of the web client to get the information from web server is OK because I can see printed in console this:

RPi-Monitor

Temperatura: 26.9 C
Humedad: 33.4 %

But in the lcd I only get this lines:

Sensor RPI-Monitor

temperature
humidity

I should expect the same lines "Temperatura" and "Humedad" with your values as in console to be showed in the lcd... but it doesn´t work.

Could you help me please?