OK, I have no experience with Actel parts.



Sounds like his clock was on a non-global resource.



A handful of resources are device- or family-dependent.

The number of global low-skew (clock) lines differs between families, but most designs use only one or two clocks, and I've never seen an instance where a signal global clock failed to route on a global resource.

Maybe he put his clock signal on a non-clock input pin? Some families require you to use special pins for clocks.

Other family-dependent resources include differential signal on pins (RTFDS), DDR, clock management (DLL/PLL) and some memories which require instantiation instead of inference. In other words, if you can write a behavioral description, from which the tools can infer the logic, even if the tools build the logic out of gates and flops rather than use a special resource, then the code is portable. If you have to pull a part out of a vendor library, it's not.



Either written incorrectly or not paying attention to which pins are which.

-a