hi ,

i have a probelm while i am using the DCM for clock mutiply. i am
using single DCM for my virtex 2 pro device. i have two sub modules
and a top module. i need to use DCM in all the 3 modules (2 sub
modules and top module). so i invoked dcm and component instantiation
in all the 3 modules. but i am facing the problem while i am mapping .
its throwing the error... like

error: ERROR:LIT - IPAD symbol "clk77p76" is driving more than one
loads. IPAD can only
   drive a single IBUF or two IBUFDS. If you are using a  BUF instead
of an
   IBUF, it may have been simplified, please use an explicit IBUF
instead.

can my dcm clk cannnot drive more than 2 loads .....

regards
srik

<e...@gmail.com> wrote in message 
news:1...@j4g2000prf.googlegroups.com...
> hi ,
>
> i have a probelm while i am using the DCM for clock mutiply. i am
> using single DCM for my virtex 2 pro device. i have two sub modules
> and a top module. i need to use DCM in all the 3 modules (2 sub
> modules and top module). so i invoked dcm and component instantiation
> in all the 3 modules. but i am facing the problem while i am mapping .
> its throwing the error... like
>
> error: ERROR:LIT - IPAD symbol "clk77p76" is driving more than one
> loads. IPAD can only
>   drive a single IBUF or two IBUFDS. If you are using a  BUF instead
> of an
>   IBUF, it may have been simplified, please use an explicit IBUF
> instead.
>
> can my dcm clk cannnot drive more than 2 loads .....
>
> regards
> srik
>

You only need to instantiate a DCM in the top module.