2. Support
  3. AR# 1067: FPGA/CPLD/PROM - What does the ordering part number of Xilinx devices mean? What does each portion of the part mark on a Xilinx device mean?
  4. AR# 10677: 3.1i Foundation ISE ECS Schematic Capture - I/O buffer macros give NGDBuild errors: 463,455,466,467

AR# 10677

3.1i Foundation ISE ECS Schematic Capture - I/O buffer macros give NGDBuild errors: 463,455,466,467

Description

Keywords: WebPACK, obufe, obuf, ibuf, NGDBuild, NGD, Build, buffer, 463, 455,
466, 467, 9500

Urgency: Standard

General Description:
I/O buffer macros (ibuf 4,8,16; obuf 4,8,16; and obufe 4,8,16) give one of the following
errors or warnings:

ERROR:NgdBuild:455 - logical net 'xxx' has multiple drivers
WARNING:NgdBuild:463 - input pad net 'xxx has an illegal input buffer
ERROR:NgdBuild:466 - input pad net 'xxx' has illegal connection
ERROR:NgdBuild:467 - output pad net 'xxx' has an illegal buffer

Solution

1

Use multiple instances of single-buffer primitives instead of buffer macros.

To determine if a library element is a macro or a primitive, refer to the Libraries Guide
on support.xilinx.com.

2

Use individual primitives (ibuf, obuf, obufe) instead of the bulk buffers.
AR# 10677
Date 10/21/2002
Status Archive
Type General Article