Modular HD44780 LCD drivers for lcdproc

Download

Binary based on LCDproc v0.4-pre9	For those who couldn't be bothered compiling. This supports four lcd wirings - 4bit, lcdtime's 8bit, winamp and serial LPT connections.
source files (multiple files)	Download then untar from the lcdproc directory. e.g. cd lcdproc-0.4-pre9; gzip -cd lcdproc-hd44780-100100.tgz \| tar xvf -; make
source file (single hd44780.c file)	Not so modular but for those who can't stomach multiple files :-).

multiple displays can be stacked up to form a single "virtual" display. For example, a 4, 2 and 1 line display can be used to form a 7 line display. The number of displays is limited by the individual HD44780 driver.
The 4bit driver now supports up to 7 displays so you could have a 28 line display :-).
Added support for the LCD and LED bargraph combination from lcdtime.
command line support for your particular HD44780 driver and for using another port address (no need to recompile just to change parallel ports).

adding support for another HD44780 variant is much easier - you typically only need to write two small functions (10-50 lines).
the code is much more maintainable as adding support for a new connection doesn't affect the code for other connections
no need to recompile when changing parallel ports or connections
the code has been cleaned up :-)

When specifying the lcd size, do so before the -d argument.
Arguments that need to be passed to the driver should be in quotes after the -d HD44780 arguments.
Use the "-e" argument for extended interfaces (e.g. >= 3 displays).

LCDd -t 16x2 -d HD44780 "-p 0x278"

LCDd -t 40x4 -d HD44780 "-v 2,2"

LCDd -t 20x3 -d HD44780 "-c winamp -v 2,1"

LCDd -t 16x7 -d HD44780 "-v 2,4,1"

For help on the parameters for the 8-bit driver (make sure --help is the last arguments in quotes):

LCDd -d HD44780 "-c 8bit --help"

Work out how your LCD is wired up .... see the wiring section below.
What parallel port? If you have only one then try "-p 0x378". If it's connected to a second parallel port try "-p 0x278".

See doc/hd44780_howto.txt in the lcdproc distribution. For displays 2-7 refer the source code.

Not all lcdproc modes support > 4 lines - until there is full support in the clients this may cause some problems for multiple displays with lines > 4.

Email blt@ieee.org