AR# 4535

1.5 HITOP- hi429 - Cannot apply TIMESPEC on what seems to be a valid timespec

Description

Keywords: hi429, 9500xl, TIMESPEC

Urgency: Standard

General Description: Even though the timespec has a valid path or group, the
fitter may issue this warning:
WARNING: hi429 - Cannot apply TIMESPEC TS_ADDR_TO_A1_CS =
MAXDELAY:FROM:ADDR:TO:A1_CS:10.000000 nS because of one of the
following: (a) a signal name was not found; (b) a signal was
removed or renamed due to optimization; (c) there is no path
between the FROM node and TO node in the TIMESPEC.

Solution

The original TIMESPEC from the constraints editor looks like, for example:

NET "A1_CSB_" TNM = "A1_CS";
TIMEGRP "ADDR" = PADS("ADDR<*>");
TIMESPEC "TS_ADDR_TO_A1_CS" = FROM "ADDR" TO "A1_CS" 10.000000 ns;

If it is added in the design.ucf as shown below, it works:

TIMESPEC "TS_ADDR_TO_A_CS" = FROM PADS(ADDR*) TO PADS(A1_CSB_) 10.000000 ns;


The "" around the signal qualifier "ADDR<*>", i.e. TIMEGRP "ADDR" = PADS("ADDR<*>")
should be "ADDR" = PADS(ADDR<*>). The workaround is to remove the "" around the
signal qualifier.

This is fixed in the 3.1i version of the Xilinx CPLD Fitting Software.
AR# 4535
Date 08/27/2001
Status Archive
Type General Article