Velocity Reviews - Computer Hardware Reviews

Velocity Reviews > Newsgroups > Programming > VHDL > Discrepancy in CLB Usage Report

Reply
Thread Tools

Discrepancy in CLB Usage Report

 
 
Anand P Paralkar
Guest
Posts: n/a
 
      07-02-2003
Hi,

I am using the following flow:

VHDL - Entry
Synplify Pro - Synthesis
Xilinx Design Manager - Post synthesis, place and route, etc.

The target device is Xilinx Spartan XL - XCS20XL.

I am trying to understand the two summaries:

1. Synthesis Summary
--------------------
Logic Mapping Summary:
FMAPs: 243 of 392 (62%)
HMAPs: 83 of 196 (43%)
Total packed CLBs: 173 of 196 (89%) <-*-*-*-
(Packed CLBs is determined by the larger of three quantities:
Registers / 2, HMAPs, or FMAPs / 2.)

2. Xilinx Design Manager Summary
--------------------------------
Design Summary:
Number of errors: 1
Number of warnings: 6
Number of CLBs: 250 out of 196 127% <-*-*-*-
CLB Flip Flops: 346
CLB Latches: 3
4 input LUTs: 246
3 input LUTs: 230 (147 used as route-throughs)
Number of bonded IOBs: 48 out of 112 42%
IOB Flops: 34
IOB Latches: 0
Number of clock IOB pads: 4 out of 8 50%
Number of TBUFs: 2 out of 448 1%
Number of BUFGLSs: 4 out of 8 50%
32 unrelated functions packed into 31 CLBs.
(12% of the CLBs used are affected.)
Total equivalent gate count for design: 4178
Additional JTAG gate count for IOBs: 2304
-------------------------------------------------------------------

Why is there a discrepancy between the Number of CLBs reported
by the synthesis tool (173) and the Xilinx design manager (250)?

As you would observe, the design manager reports an error due
to the excess usage of CLBs. As a result the flow does not proceed
to Place and Route etc. Any suggestions?

Thank you for your time.

Thanks,
Anand

 
Reply With Quote
 
 
 
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Exam 70-123: Is the "discrepancy report" the final product of SAM? Charles Kerekes Microsoft Certification 0 08-04-2006 06:17 PM
Discrepancy between flow-packets and interface counter Garry Glendown Cisco 9 04-20-2005 08:38 PM
reduce the CLB DAvid VHDL 2 10-24-2004 05:15 PM
Static Access Discrepancy? Paul Carey Java 1 01-16-2004 10:55 AM
Time discrepancy between java and native Gopal Java 4 10-30-2003 05:37 PM



Advertisments