@Rajagra:
Yep, I understand that USB has its own scancode set / protocol, however the keyboard needs to know how to send a PS/2 scancode set when it's operating in PS/2 mode (e.g. with the adapter). The computer should have nothing to do with this save negotiating the protocol it wants.
@skriefal:
There are at least 3 'standard' PS/2 scan code sets. Set 2 is the de facto standard for PCs these days but 3 is also used sometimes (e.g. for older SGI machines). Typically, the PS/2-only keyboards will do all three sets while the cheapie USB keyboards with PS/2 support added as an afterthought seem to only do set 2. I'm hoping the FILCOs are better than those cheapie boards in more than just build quality.