The lazwiringpi wrapper has worked fine for me in the past, found here (you must be logged in to see the download).
This wrapper allows you to accessing the Raspberry Pi wiringPi library which is written in C.
Granted, it has been over a year since I last used it, but as of today I can no longer link to this library. I get the errors:
/usr/bin/ld: error: raspberry uses VFP register arguments, ./wiringPi/wiringPi.o does not /usr/bin/ld: failed to merge target specific data of file ./wiringPi/wiringPi.
After a few hours of stumbling around I managed to get it running by recompiling the underlying C wiringPi.c library.
It was a simple matter of cd’ing to the correct wiringPi directory and simply typing:
gcc -c wiringPi.c
This recompiles the C library and the new pascal code will correctly link to it. Recompiling is the best bet since it takes into account any other recent changes as well.
If you are unable to make recompilation work, I updated the original lazwiringPi archive with the wiringPi.o file that is linking properly for me here: