Marc Randolph <[email protected]> wrote in message news:<[email protected]>...
> Moti Cohen wrote:
> > Hy all,
> > I'm currently implementing a receiver (vhdl) part of the ethernet mac
> > which is responsible for the MII interafce. I'm need an crc32
> > calculator (RTL) to check the FCS field. I've tried using the easics
> > crctoll in order to create the mechanism (for a 4 bit data input) but
> > it does not seems to work. does anyone have a working (rtl) vhdl
> > implementation for this block? or at least a detailed expalnation on
> > how to create it..?
>
> Howdy Moti,
>
> I'd be willing to bet that your problem is bit ordering (hint: take
> an 8 bit chunk and reverse the order of the bits before throwing it into
> the easics checker). Although I'm sure there is probably a way, I don't
> quickly see how you'd do it four bits at a time.
>
> Good luck,
>
> Marc

Hi Marc,
Thanks for your answer so first of all I have already tried revesring
the bits order without any success - I read something about a "magic
number" but I'm not sure what to do with it. regarding the 4 bit data
path - the easics "crctoll" can generate a vhdl file for 1,2,4,8...64
bits so its not the problem..