VFD-WCN is a Python library for driving multiple Wincor Nixdorf (WCN) Point of Sale USB Vacuum Fluorescent Display (VFD), such as BA-63 USB. This library should be compatible with any WCN BA-6x USB VFD.
BA 63 model, from Wincor Nixdorf web site
More information on VFDs is available in Wincor Nixdorf documents:
- Character sets
- Operating manual (including escape sequences)
Please note that VFD-WCN is mainly an extension of VFD-POS library from https://github.com/antonio-fr/VFDPoS Many thanks to Antoine Ferron for the work.
The library provides high level abstraction to use Wincor Nixdorf Point of Sale VFD USB
- identification of each display as well as information on type and capability (2 ou 4 lines of display)
- Easy to use and handle, play with your VFD in no time
- Cross-platform code and dependencies
- Full python code to access VFD through USB
- Character encoding automatic conversion
- limited python dependencies (some provided in zip)
This library needs PyUSB, it can work on mutiple OS platform. PyUSB always requires libusb.
PyUSB is installed through pip <https://pypi.python.org/pypi/pyusb>:
pip install pyusb
On Debian based distributions
sudo apt-get install libusb-1.0-0-dev
On Fedora (replace dnf by yum for older version of RedHat based distributions)
sudo dnf install libusb1-devel
In windows instead of this library you can use VFD-POS, from which VFD-WCN is inspired but provides driver-less, null installation and platform specific access to a single VFD. https://github.com/antonio-fr/VFD-POS
If you need universal and cross-platform Python code, you can still use this library. On Windows, this requires libusb-win32 driver installed and loaded for the WN VFD. The easiest way is to get Zadig and to select libusb-win32 for the Diplay Interface of your WN VFD. http://zadig.akeo.ie/ Then you need PyUSB (provided in zip release).
pip install git+https://github.com/stephanemouton/VFD-WCN.git
To use the library, add the following import in your code
from vfdpos import *
A Factory pattern is used to create instances of multiple connected displays according to devices dicovered by libusb. The kind of device to find can be specified as parameter of the factory (by default, BA63 2 lines displays). The vfdpos.py define constants (BA63 & BA66) for display types which are USB product IDs
factory=WincorNixdorfDisplayFactory()
VFDs = factory.get_vfd_pos()
MyVFD = VFDs[0]
Tell the VFD to perform self-test. You may need to initialize VFD again after do so.
MyVFD.selftest()
Tell the VFD to perform a reboot. You need to initialize VFD again after do so.
MyVFD.reset()
Set the VFD charset. See your WN operational manual documentation for char code. During initialisation, WN VFD is automatically set up to 0x31 = Code Page 850. Don't change it unless you really have specific need, this would cause issues with write_msg function.
Character tables are available in : http://www.wincor-nixdorf.com/internet/cae/servlet/contentblob/614268/publicationFile/60592/BA6x_Character_Appendix_english.pdf
MyVFD.set_charset(CHARSET_CODE)
Clear and erase the VFD screen.
MyVFD.clearscreen()
Print a character from its number at the cursor position
MyVFD.printchr(CHAR_CODE)
Change the position of the cursor to a given column and line. If 0 is provided for a parameter, no change is performed for it.
MyVFD.poscur(LINE, COLUMN)
Write a message to the VFD screen at the cursor position. This function uses automatic decoding of any unicode character. In case you provide direclty the string don't forget trailing u ( u"string" ). If you change the charset to another one, this function might bring some issues. You can use "\r" and "\n" inside the string to get line control.
MyVFD.write_msg(MESSAGE_STRING)
When python program stops, the display keep lighting. This command clears the display. Useful if you need to light off the VFD after using it.
MyVFD.close()
Form more details: see code in examples directory
The following example displays a basic text on a BA66 USB VFD, assuming only a single display is connected.
from vfdpos import *
factory=WincorNixdorfDisplayFactory()
wnpos = factory.get_vfd_pos(BA66)
wnpos.write_msg("Hello World !\r\nThat works :)")
raw_input("PRESS ENTER TO EXIT")
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 3 of the License.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.