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DCM CLK driving load problem

Started by ekav...@gmail.com July 14, 2007
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

<ekavirsrikanth@gmail.com> wrote in message 
news:1184395776.985541.34040@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.