Have you tried the parallel port tester:
LinuxCNC Documentation Wiki: Parallel Port Tester
This allows real time reading of the inputs and toggling the outputs to check your breakout
You may have to edit ptest.hal to change the port address, its default is 0x378
( "0" is a good choice if you have a plug-in parallel port card with unknown address, "0" means the first parallel port found )
also here's a video that shows the DB25-1205 breakouts 5V power setup: