Re: [myhdl-list] about MEP 107

[Christopher F. <chr...@gm...>]

On 8/10/12 9:27 AM, Jose Ignacio Villar wrote:
> Hi all,
> I'd like to know about the current status of MEP 107 or if there is
> someone working on it, since I could understand from some messages in
> the list that at least part of the work might be in progress.

Sorry for the late reply, I have been extremely busy and
will continue to be occupied for a couple months.  Best
of my knowledge, I have updated the MEP with the latest
comments and there are no major objections.  The MEP has
been proposed and informally accepted(?).  I believe, we
are ready to move forward with the implementation.  Other
than basic feasibility experiments I have not made
progress on the implementation.

It should be noted, while we were discussing the MEP it
was noted that "interfaces" can be implemented in version
0.7 but you have to locally reference the Signals in the 
interface/container.  The following is an example of
locally referencing the signals.

     def complex_mult(clock, reset, a, b, c):
         a_real,a_imag = a.real,a.imag
         b_real,b_imag = b.real,b.imag
         c_real,c_imag = c.real,c.imag

         @always_seq(clock.posedge, reset=rest)
         def hdl():
             c_real.next = (a_real*b_real) + -1*(a_imag*b_imag)
             c_imag.next = (a_imag*b_real) + (a_real*b_imag)

         return hdl


The full example available here : http://bit.ly/QpEm5j
I also have a larger example here : http://bit.ly/QMhDuP,
this example might not be of much use without some description?

When MEP 107 is implemented the above can be expressed as:

     def complex_mult(clock, reset, a, b, c):

         @always_seq(clock.posedge, reset=rest)
         def hdl():
             c.real.next = (a.real*b.real) + -1*(a.imag*b.imag)
             c.imag.next = (a.imag*b.real) + (a.real*b.imag)

         return hdl


If someone wants to use interfaces today, I don't think
the local references is (should be) a huge deterrent. Some
have indicated they prefer the local references.

Hope that helps,
Chris