2. 技术支持
  3. AR# 32987: 11.1 MAP, Virtex-6/ Virtex-5/ Spartan-6 - What options are available that allow two SRL16s to be combined into one LUT Complex?

AR# 32987

11.1 MAP, Virtex-6/ Virtex-5/ Spartan-6 - What options are available that allow two SRL16s to be combined into one LUT Complex?

描述

I would like MAP to combine two SRL16s into a single LUT Complex. How can this be done?

解决方案


For manual control of SRL16 LUT sharing, two SRL16s can be constrained to the same LUT Complex by assigning each the same LUTNM property as follows :

INST "SRL16E_0" lutnm = group_1;
INST "SRL16E_1" lutnm = group_1;

Automatic LUT sharing for SRL16s is being introduced in ISE version 11.2. The following describes the behavior of the three affected device families:

Virtex-6
Default is "AUTO", other values are "AREA" and "OFF"
The value can be changed with the following variable:
setenv XIL_MAP_SRL_COMPRESSION AREA (Linux)
SET XIL_MAP_SRL_COMPRESSION=AREA (Windows)

Spartan-6
Default is "AREA", other values are "AUTO" and "OFF"
The value can be changed with the following variable:
setenv XIL_MAP_SRL_COMPRESSION AUTO (Linux)
SET XIL_MAP_SRL_COMPRESSION=AUTO (Windows)

Virtex-5
Default is off. When turned on, this feature is equivalent to AREA mode.
The feature can be turned on with the following variable:
setenv XIL_MAP_SRL_COMPRESSION 1 (Linux)
SET XIL_MAP_SRL_COMPRESSION AUTO=1 (Windows)
NOTE: Unset the variable to turn this feature off for Virtex-5. Do not use "0" as any value is considered to be "on".

链接问答记录

相关答复记录

Answer Number 问答标题 问题版本 已解决问题的版本
37213 Virtex-6 FPGA Design Assistant - Troubleshoot common fabric problems N/A N/A
AR# 32987
日期 12/15/2012
状态 Active
Type 综合文章
器件 More Less
Tools More Less