AR# 3016

M1 TNM placed on net between PAD and BUFG/IBUF not forward traced

Description

Keywords: TNM, propagate, forward trace

Urgency: standard

General Description:

For the following arrangement:

IPAD -- clockpad -- IBUF -- clock



Placing a TNM on "clockpad" will not forward propagate the
TNM to all flip-flops this net goes to.

Solution

1

A TNM must be placed on
the output of the clock buffer (BUFG,BUFGP,BUFGS,BUFGLS,BUFGE)
or the input buffer (IBUF) for forward propagation to occur:

NET clock TNM = mygroup;


2

There is a new constraint for M1.5 called TNM_NET. If you replace TNM with TNM_NET it will trace through the buffer to the next synchronous element.
AR# 3016
Date 04/03/2000
Status Archive
Type General Article