Re: VHDL refactoring tools

On Jun 21, 11:41 am, Mike Treseler <mtrese...@xxxxxxxxx> wrote:
I agree with Jonathan about procedural rather than
structural decomposition. The base function of
a crc check is just a shift with a twist, and
adding procedural layers is something the vhdl
language is good for. VHDL synthesis works better
than most designers believe.

-- Mike Treseler

Am I missing something? Procedural interfaces still require data to be
passed in and out, but if the needed data was not passed, the same
problem exists. Unless you go to global signals, where there is no
hierarchy at all, or you use one huge file to take advantage of local
scope (always defining procedures inside the scope of the procedure in
which they are called), procedures vs entities don't appear to make a
difference. Both methods (globals and entirely local scope) have been
discredited in SW and HW design for a long time. Actually, one
language (ada, from which much of vhdl was borrowed) allows a
procedure to be locally declared and externally implemented in a
separate file, but I don't know if that eliminates local scope

The ability to "containerize' the interface (procedure or entity),
like running virtual conduit through a building's walls, allows one to
add/subtract interface elements, without having to tear into the
intervening walls. And VDHL "conduits" (record types), unlike real
ones, never "fill up". They just don't currently have a flexible means
of defining directionality (port modes).