The new addition to this release is a module to drive hd44780  compatible LCD displays (in 4bit parallel mode) from the Raspberry Pi GPIO interface. It is an original Python module from Adafruit  converted to Lua, sample usage is in `test_lcd.lua` .
Code available from the Github repo , or through LuaRocks; `sudo luarocks install rpi-gpio`
From: Thijs Schreijer
The rpi-gpio module is available in the luarocks repository and can be installed (on Raspberry Pi only) using `sudo luarocks install rpi-gpio`.
The module provides support for the Raspberry Pi builtin General Purpose Input Output (GPIO) interface, and allows you to create and control electronics projects from Lua.
It is a binding to the code of Ben Croston (Python GPIO module) , based upon the works of Andre Simon  and further extended by me. Where Andres’ Lua binding code only supported basic input output pins, the module now supports all features of the Python module.
- basic input/output pins
- PWM support (software based)
- edge detection (falling/rising/both)
- asynchronous callbacks based on edges
Examples  for all of these are available in the repo  to get going quickly.
Not in the python module, and hence not in the Lua binding (a.o.)
- hardware PWM
But I intend to add those as they come available in the Python module
The asynchronous callbacks are implemented using darksidesync  which is not a rock dependency, so you’ll have to manually install it using `sudo luarocks install darksidesync` (but only if you intend to use callbacks). See example 6  on how to use those (also requires the ‘copas’ module)
Best way for a quick start is through the Lua readme  and the examples .
Enjoy! And as always comments are welcome!