Use hd44780 LCD with lcd2usb


6 posts
by m1m1 » Mon Jun 25, 2012 6:30 pm
Hi,
as I was asked at Twitter, I wanted to let you know how I managed to get a 20x4 character lcd to work with the Raspberry Pi.

First of all, it's a display with a HD44780 controller, so originally designed for the lpt port. There exists a open-source project named lcd2usb at
http://www.harbaum.org/till/lcd2usb/index.shtml
to connect these displays via USB.
From lcdmodkit you can buy displays complete with an lcd2usb adapter ready for USB, as I did.

The displays come with an internal USB connector. Because the Raspberry Pi does not have internal USB ports on it's board, I cut a standard USB cable open and soldered the four wires together. That was the only hardware modification I had to do.

XBMC has support (only) for lcdproc. From this point, there is no difference in installing and configuring lcdproc for a normal linux pc.

If you have further questions ask them, I could provide the config files, but there is no magic.

ImageImage
Posts: 6
Joined: Mon Jun 25, 2012 6:28 pm
by kghunt » Tue Jun 26, 2012 8:15 pm
I have a similar LCD and I got it working without lcdproc or any other program. I wrote a simple driver in python that sends hex commands to the LCD over the USB serial interface. It is pretty easy to do and a good project for learning python.
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Joined: Sun Mar 04, 2012 9:28 am
by matt@shagshaw.com » Mon Jul 23, 2012 7:19 pm
Hiya

I have had a lcd2usb with 20x4 display for ages, and the lcdproc list were absolutely no help in getting it configured, so it has gone unused for about a year

I could do with the lcdproc config file, to compare to what I have tried. Apparently it is also on a very old firmware revision, but I couldn't find a file or method of upgrading to the latest firmware, and the list seemed to think it was that stopping it working, but wouldn't offer any solution

It would be great if I could finally get this going !!!!!

You can contact me off list if you like, matt@shagshaw.com

Thanks !!!!
Posts: 21
Joined: Thu May 31, 2012 8:04 pm
by TarjeiB » Tue Jul 24, 2012 3:19 pm
Interesting! I have a LCD2USB device but it's not giving me an entry in /dev.

Could you elaborate a bit on what you did to make it work? I'm getting
Bus 001 Device 005: ID 0403:c630 Future Technology Devices International, Ltd lcd2usb interface
in lsusb but can't find any related /dev entry.

What distribution are you using? Did you build your own kernel?
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Joined: Thu Jul 12, 2012 3:33 pm
by TarjeiB » Tue Jul 24, 2012 4:22 pm
Scratch that... "ConnectionType=lcd2usb" and all works.
I don't like magic! I want a device ;)
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Joined: Thu Jul 12, 2012 3:33 pm
by robwriter » Thu Aug 16, 2012 9:10 pm
I've no doubt that I'm missing something obvious, but mine doesn't work. It does on windows, but I can't get it to work on linux.

Can anyone explain exactly what combination LCDd/lcdproc should produce an output?
Posts: 108
Joined: Sat Feb 25, 2012 6:26 pm