Years ago I used to have a HD44780 20x4 LCD attached to a media PC via parallel; travel years down the line and we have a HTPC setup which does not have a parallel port.
Reading up on the use of standard USB to parallel convertors as can be bought on ebay etc... most of which will not work with anything other than a printer as they do not support bitbanging.
Something that I have discovered is that a micro controller can be used to bridge the two devices, mimicking something like the Matrix Orbital USB character displays for use with LCD Smartie. Past this, the information I have found is quite limited other than the fact that it can be done and people do use it.
Does anybody know of any information or guides on how to use an Arduino in this way; either connecting a HD44780 in 8-bit mode or via an i2c backpack?
It would be helpful if you described what you really wanting to do.
What are you really trying to do? Hook an LCD up to your media center for additional information?
If so, we need more information like what type of media center s/w and what OS and what i/o ports are available on your media center.
like does it have serial ports, usb ports etc... and if it as USB ports does it support virtual serial ports?
In terms of LCD smartie if you google around there many pages that show how to implement LCD smartie support using an Arduino and an LCD and then you would need to read up on your media center s/w to see if it supports LCD smartie.
I have a library called hd44780 (which is available in the IDE library manager) that includes an example sketch for using an arduino with a LCD for lcdproc so you can display all kinds of system information about your linux machine.
The hd44780 allows arduino sketches to control a hd44780 using a variety of interfaces like pins, or i2c.
You can read more about hd44780 here: GitHub - duinoWitchery/hd44780: Extensible hd44780 LCD library
I currently don't have an lcd smartie sketch, but it is on my list to do and include in the hd44780 library package.
I have managed to get a solution working using the code available from Miles Burton.
Although I have previously tried this code, all that was being displayed on the screen was a series of numbers; since then I have discovered that the code works if compiled and uploaded using Arduino IDE 00xx, rather than the latest IDE.
For reference, the computer in question is running Windows 10 64-Bit and only has USB ports, with no serial or parallel ports (or headers on the motherboard).