AR# 4419

M1.4: Map FATAL_ERROR:baste:bastetspec.c:2402:1.69.14.3 - NET OFFSET 'IN1 IN : 20000.00 pS : BEFORE : CLK' has no data IOBCOMP.

描述

Keywords: Bastetspec, NET OFFSET, IOBCOMP,map, timespec, xc5200

Urgency: standard

General Description

When running a XC5200 design through M1.4, you may get following map error:

FATAL_ERROR:baste:bastetspec.c:2402:1.69.14.3 - NET OFFSET 'IN1 IN : 20000.000000 pS : BEFORE : CLK' has no data IOBCOMP. Process will terminate. Please call Xilinx support.

解决方案


This is could be due to a bug in Map. This is currently scheduled to be fixed in M2.1.

The workaround is not to use OFFSET timing constraint.
Instead, use FROM:TO timespec. For example comment out the OFFSET constraint and add the last two lines:


NET clk PERIOD = 40 ;
//NET "IN1" OFFSET = IN 20 before "CLK"; <== DO NOT USE

TIMEGRP input1 = PADS (IN1);
TIMESPEC TS01 = FROM: input1: TO: FFS: 20;


There is one draw back.

For OFFSET IN, the pad to flop delay is reduced by the pad to clk delay. The user must manually adjust for this when using a FROM:TO. If the user chooses not to adjust the delay, the FROM:TO is overly conservative.

For OFFSET OUT, the flop to pad delay is added to by the pad to clk delay. The user must manually adjust for this when using a FROM:TO. If the user chooses not to adjust the delay, the FROM:TO is not conservative enough.





AR# 4419
日期 04/03/2000
状态 Archive
Type 综合文章