EDIflat_11_1.lab

®

Encounter Digital Implementation (Flat) Versio n 11.1 Lab Manual

June Ju ne 18, 2012 2012

 1990-2012 Cadence Design Systems, Inc. All rights reserved. Printed in the United States of America.

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Confidentiality Notice No part of this publication may be reproduced reproduced in whole or in part by any means (including photocopying photocopying or storage in an information storage/retrieval system) or transmitted in any form or by any means without p rior written permission from Cadence Design Systems, Inc. (Cadence). Information in this document is subject to change without notice and does not represent a commitment on the part of Cadence. The information contained herein is the proprietary and confidential information of Cadence or its licensors, and is supplied subject to, and may be used only by Cadence customers in accordance with a written agreement between Cadence and its customers. Except as ma y be explicitly set forth in such agreement, Cadence does not make, and expressly disclaims, any representations or warranties as to the completeness, accuracy or usefulness of the information contained in this document. Cadence does not warrant that use of such information will not infringe any third party rights, nor does Cadence assume any liability for damages or costs of any kind that may result from use of such information. RESTRICTED RIGHTS LEGEND Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraph (c)(1)(ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.227-7013. 252.227-7013. UNPUBLISHED This document contains unpublished confidential information and is not t o be disclosed or used except as authorized by written contract with Cadence. Rights reserved under the copyright laws of the United States.

ii

Cadence Design Systems, Inc.

06/18/12

 1990-2012 Cadence Design Systems, Inc. All rights reserved. Printed in the United States of America.

Cadence Design Systems, Inc., 2655 Seely Avenue, San Jose, CA 95134, USA

Cadence Trademarks Trademarks and service marks of Cadence Design Systems, Inc. (Cadence) contained in this document are attributed to Cadence with the appropriate symbol. For queries regarding Cadence trademarks, contact the corporate legal department at the address above or call 800.862.4522. 1st Silicon Success®

InstallScape™

Silicon Ensemble®

Allegro®

Invisible Specman®

Silicon Express™

Accelerating Mixed Signal Design®

IP Gallery™

SKILL®

Assura®

Nano Encounter ®

SoC Encounter ™

BuildGates®

NanoRoute®

SourceLink ® online customer support

Cadence®

NC-Verilog®

SPECCTRA®

Concept®

NeoCell®

SPECCTRAQuest®

Conformal®

NeoCircuit®

Specman®

Connections®

Neo Circuit - RF®

Specman-Elite®

Diva®

NeoIP®

Spectre®

Dracula®

OpenBook ® online documentation library

SpeedBridge®

ElectronStorm®

OrCAD ®

Verifault-XL®

Encounter ®

Palladium®

Verification Advisor ®

EU CAD®

Pearl®

Fire & Ice

®

First Encounter ® ®

Verilog® ®

PowerSuite PSpice®

Virtuoso® VoltageStorm®

®

HDL-ICE

SignalStorm

Incisive®

Silicon Design Chain™

Xtreme®

Other Trademarks Open SystemC, Open SystemC Initiative, OSCI, SystemC, and SystemC Initiative are trademarks or registered trademarks of Open SystemC Initia tive, Inc. in the United States and other countries and are used with permission. All other trademarks are the property of their respective holders.

Confidentiality Notice No part of this publication may be reproduced reproduced in whole or in part by any means (including photocopying photocopying or storage in an information storage/retrieval system) or transmitted in any form or by any means without p rior written permission from Cadence Design Systems, Inc. (Cadence). Information in this document is subject to change without notice and does not represent a commitment on the part of Cadence. The information contained herein is the proprietary and confidential information of Cadence or its licensors, and is supplied subject to, and may be used only by Cadence customers in accordance with a written agreement between Cadence and its customers. Except as ma y be explicitly set forth in such agreement, Cadence does not make, and expressly disclaims, any representations or warranties as to the completeness, accuracy or usefulness of the information contained in this document. Cadence does not warrant that use of such information will not infringe any third party rights, nor does Cadence assume any liability for damages or costs of any kind that may result from use of such information. RESTRICTED RIGHTS LEGEND Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraph (c)(1)(ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.227-7013. 252.227-7013. UNPUBLISHED This document contains unpublished confidential information and is not t o be disclosed or used except as authorized by written contract with Cadence. Rights reserved under the copyright laws of the United States.

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Table Ta ble of Cont ents Encounter Digital Implementation (Flat) Module 1:

Ab ou t Thi T hi s Co ur se

Lab 1-1

Locating Cadence Online Support Solutions .................... .................................. ............................ ............................ ........................... ...............1-1 ..1-1

Lab 1-2

Customizing Notification and Search Preferences ........................... ......................................... ............................ ...........................1-3 .............1-3

Module 2:

Design Import and Floorplanning

Lab 2-1

Importing a Design...................... Design.................................... ............................ ............................ ............................ ............................ ............................ ...........................2-1 .............2-1 Design Design Information Information ............................ .......................................... ............................ ............................ ............................ ............................ ............................ ......................2-1 ........2-1 Starting the Software ......................................................................................................................2-1 Importing Importing a Design............... Design............................. ............................ ............................ ............................ ............................ ............................ ............................ ......................2-1 ........2-1 Viewing Viewing the Design............................ .......................................... ............................ ............................ ............................ ............................ ............................ ......................2-2 ........2-2 Viewing the Design Hierarchy .......................................................................................................2-5

Lab 2-2

Using Bindkeys ............................ .......................................... ............................ ............................ ............................ ............................ ............................ ...........................2-7 .............2-7 Using the Bindkey Form ................................................................................................................2-7 Using Bindkeys Bindkeys ........................... ......................................... ............................ ............................ ............................ ............................ ............................ ........................... ...............2-8 ..2-8

Lab 2-3

Tearing Off Menus ........................... ......................................... ............................ ............................ ............................ ............................ ............................ ....................2-11 ......2-11

Lab 2-4

Clearing the Floorplan..................................... ................................................... ............................ ............................ ............................ ............................ ..................2-12 ....2-12

Lab 2-5

Initializing the Floorplan .......................... ........................................ ............................ ............................ ............................ ............................ .........................2-13 ...........2-13

Lab 2-6

Customizing the Menus ............................ .......................................... ............................ ............................ ............................ ............................ .........................2-15 ...........2-15

Lab 2-7

Checking the Design......................... Design....................................... ............................ ............................ ............................ ............................ ............................ ....................2-17 ......2-17

Lab 2-8

Floorplanning a Design...................................... .................................................... ............................ ............................ ............................ ............................ ................2-18 ..2-18 Floorplannin Floorplanning g ............................ ......................................... ........................... ............................ ............................ ............................ ............................ ............................ ................2-18 ..2-18 Relative Floorplanning .................................................................................................................2-21 Automatic Floorplanning Synthesis for Block Placement ...........................................................2-23 Adding a Block Halo....................................................................................................................2-24 Power Power Planning Planning ........................... ......................................... ............................ ............................ ............................ ............................ ............................ ........................... .............2-26 2-26 Preplacing a Cell with the Design Browser .................................................................................2-31 Creating Followpin Routing with Special Route .........................................................................2-33 Clearing Floorplan Objects ..........................................................................................................2-35 Saving the Session .......................................................................................................................2-35

Module 3:

Placement Placement and Trial Route

Lab 3-1

Running Placement ............................ .......................................... ............................ ............................ ............................ ............................ ............................ ....................3-1 ......3-1

Lab 3-2

Running a Trial Route................................... ................................................. ............................ ............................ ............................ ............................ ......................3-6 ........3-6 Viewing Routing Congestion .........................................................................................................3-6 Saving the Design ..........................................................................................................................3-8 Viewing a Design After a Trial Route ...........................................................................................3-8

Module 4: Lab 4-1

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Extraction, Timing Analysis, Optimi zation, zation, and CTS Extracting RC Data ........................... ......................................... ............................ ............................ ............................ ............................ ............................ ....................4-1 ......4-1 Extracting Extracting RCs ............................ .......................................... ............................ ............................ ............................ ............................ ............................ ........................... ...............4-1 ..4-1 Calculating Delays .........................................................................................................................4-2


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Lab 4-2

Running Timing Analysis and Generating a Slack Report ..................................................... 4-3

Lab 4-3

Running Timing Optimization................................................................................................... 4-5

Lab 4-4

Running Clock Tree Synthesis ................................................................................................... 4-7 Running the Synthesis ................................................................................................................... 4-7 Viewing Clock Tree Results ......................................................................................................... 4-8

Module 5: Lab 5-1

Module 6: Lab 6-1

Module 7: Lab 7-1

Module 8: Lab 8-1

Module 9: Lab 9-1

Module 10: Lab 10-1

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Generating Scale Factors fo r Extraction Extracting and Generating Scale Factors ................................................................................. 5-1 Loading the Design ....................................................................................................................... 5-1 Generating Scale Factors with External SPEF File ....................................................................... 5-1

Power Analysis Running Power Analysis............................................................................................................. 6-1 Starting the Software ..................................................................................................................... 6-1 Importing a Design........................................................................................................................ 6-1 Loading a Floorplan ...................................................................................................................... 6-1 Running Placement and Trial Route ............................................................................................. 6-1 Extracting RC Data ....................................................................................................................... 6-2 Setting the Power Analysis Mode ................................................................................................. 6-2 Running Early Rail Analysis ......................................................................................................... 6-3 Viewing Power Analysis Results .................................................................................................. 6-5

Routing and Optimizing th e Design Routing Critical Nets with Shielding and Spacing ................................................................... 7-1 Loading the Design ....................................................................................................................... 7-1 Setting Shielded and Spacing Net Attributes ................................................................................ 7-1 Routing the Nets............................................................................................................................ 7-2

Wire Editing Using the Interactive Wire Editor ............................................................................................. 8-1 Loading the Design ....................................................................................................................... 8-1 Locating the Net for Manual Routing ........................................................................................... 8-1 Using the Wire Editor ................................................................................................................... 8-4 Replacing a Via in a Design .......................................................................................................... 8-8 Reshaping a Wire ........................................................................................................................ 8-10 Forcing the Width of a Signal Wire ............................................................................................ 8-11

Verif ying a Design Using the Verify Commands in a Design................................................................................... 9-1 Loading the Design ....................................................................................................................... 9-1 Using Verify Connectivity ............................................................................................................ 9-1 Using Verify Geometry and the Influence Rule ............................................................................ 9-4

Running t he ECO Flow Loading a Design for ECO Routing......................................................................................... 10-1 Getting Started ............................................................................................................................ 10-1 Implementing an ECO in the New Netlist with a Design............................................................ 10-1


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Module 11: Lab 11-1

Module 12: Lab 12-1

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Database Commands Using the dbGet and dbSet Commands .....................................................................................11-1

Generating and Running the Foundation Flow Scrip ts Generating and Running the Foundation Flow Scripts ..........................................................12-1 Getting Started .............................................................................................................................12-1 Running the Foundation Flow Wizard .........................................................................................12-1


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Module 1:

About This Course

Lab 1-1

Locating Cadence Online Support Solutions

Lab 1-1

Locating Cadence Online Support Soluti ons

Objecti ve:

To log in to Cadence Online Support (COS) and search for inform ation about a specific i ssue. ®

You can only complete this lab if you have access to the internet and a Cadence Online Support account. If you do not, your instructor might be able to perform a demo of this lab for the class. 1. In a web browser, enter the following: http://support.cadence.com

2. Log in to Cadence Online Support with your email and password.

The Support Home page appears.

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Encounter Digital Implementation (Flat)

1-1

Locating Cadence Online Support Solutions

Lab 1-1

3. On the Support Home page, make sure the following options are selected: 

All Document Types



All Products

4. In the Search field, enter congestion and click SEARCH. A window displays the search results. 5. In the Troubleshooting Info section, click the match called: What is the meaning of the colors in the routing operation?

A window opens with a description of the problem and the solution. 6. Close the solution window. Note:

1-2

You can filter the search results by selecting specific docu ment types or products which are listed to the left of the results.


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Lab 1-2

Customizing Notification and Search Preferences

Lab 1-2

Customizing Notifi cation and Search Preferences

Objecti ve:

To set preferences so you can improve search results and receive email notification.

You can set product and other preferences for improved search results and email notification. 1. Click the My Account link. 2. Click the Notification Preferences tab. 3. On the Set Email Notification Preferences page, do the following: a. If you are interested in receiving email notifications, check the following: Send me email notifications about new product releases.

b. Click Edit Product List. Select your products of interest. c. Specify your preferred email format. d. Select the document types you are interested in and the frequency of delivery. e. Click Save. 4. Click the Search Preferences tab. 5. On the Set Search Preferences page: a. Click Use same product and document type preferences as my Notification Preferences. b. Click Save.

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1-3

Module 2:

Design Import and Floorplanning

Lab 2-1

Importing a Design

Lab 2-1

Import ing a Design

Objective:

To start the softw are and impo rt a design.

In this lab, you import a gate-level netlist and libraries into the Encounter ® Digital Implementation system and create a floorplan. You become familiar with the floorplanning and power p lanning forms and icons. You also become familiar with checking the libraries, checking the design, and using bindkeys.

Design Information The design contains almost 6000 instances, 57 I/Os, and about 6400 nets. The netlist is a hierarchical Verilog® netlist. The DMA source clock is DTMF_INST/clk . The serial port interface clock is DTMF_INST/spi_clk . The scan clock is scan_clk . The process used is the180-nanometer process technology with six layers of metal.

Startin g t he Software 1. Change to the working directory where you will run floorplanning by entering: cd FPR/ wor k

2. Start the Encounter Digital Implementation (EDI) system by entering: encount er Note:

Do not use the window where you started the software for any windowing or UNIX operations, except to communicate with the tool.

Importin g a Design 1. To import a gate-level netlist, timing constraints, and libraries, choose File – Import Design. The Design Import form appears. 2. Click the Load button. 3. Select the dtmf.globals file. Click Open. When you load the file, it fills in the fields in the Design Import window. The technology files and the ./dtmf.view file for the labs are displayed. The dtmf.view file contains pointers to the timing library and the cons traints files. The I/O assignment file dtmf.io contains directives about how to place the I/O pads around the periphery of the core area.

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2-1

Importing a Design

Lab 2-1

4. To load the design and libraries, in the Design Import window, click OK. Here is a brief description of the fields in the Design Import window.

Field

Description

Verilog files

Contains the names of gate-level Verilog netlist files.

LEF files

Library of components and physical data for the components in LEF format. Also contains routing layers and DRC rules.

IO Assignment file

This file contains the I/O pad order information to enab le the software to place the pads on the periphery of the design. If this file is not provided, the tool places the I/O pads randomly around the periphery of the design.

MMMC View Definition file

Contains pointers to timing libraries and SDC constraints files

Viewing the Design In this section, you learn more about the objects on the screen, and how to view and interpret what you see in the design window. 1. To enlarge the window, drag the corner of the window until you can see all the modules in your design, as well as all the EDI menus.

2. Select the Floorplan view. 3. Fit the design to the window by pressing the f . 4. Zoom out by pressing Shift-z or by clicking the Zoom Out icon.

2-2


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Lab 2-1

Importing a Design

The view changes.

5. Expand the design window to display all the available pull-down menus.. 6. Choose Tools – Log Viewer.

7. Select the latest Encounter log file which corresponds to this session. 8. In the Log File form, click Open. Are there any errors displayed?

Answer: _________________ 9. Close the Log Viewer. 10. To view more of the objects, click the Zoom Out icon or press Shift-z.

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2-3

Importing a Design

Lab 2-1

11. Move your cursor over the icons and notice that their functions are displayed in text boxes, as shown here.

12. On the left of the core area, select the pink module DTMF_INST .

13. To ungroup the modules, click the Ungroup icon once. Note:

Do not perform this operation more than once.

14. To see names and properties of the design objects, double-click several objects. The pink objects on the left of the core area is the module guide, whereas the green objects to the right of the core area are all the blocks (hard macros or IP) in the design. The pink guide represents modules that were defined in the imported Verilog netlist. The size of the module guides relates to the utilization of each module and the number of standard cells that the modules contain. 15. To zoom to a particular area, press and drag the right mouse button over a rectangular area. The window zooms to that area.

2-4


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Lab 2-1

Importing a Design

16. Choose Options – Set Preference. Click the Display tab. The Min Floorplan Module Size parameter determines the size of the module guides. Because the Min. Floorplan Module Size is defined as 100, if a module contain fewer than 100 instances, it will be merged into another module guide. a. To better understand the fields on the form, click Help. Most forms have a Help button to display a Cadence Help window and give you more information about the form. b. When you are finished reviewing the fields, click Cancel. 17. To regroup the modules, select one of the pink guides. Click the Group icon.

Viewing the Design Hierarchy 1. To view the hierarchical design that you imported, choose Tools – Design Browser. 2. To expand the modules, click the plus sign (+) next to Modules.

3. To expand DTMF_INST, click its plus sign (+). How many nets does it contain?

Answer: _____________ 4. To view the I/O terminals of DTMF_INST, click the Terms plus sign (+).

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2-5

Importing a Design

Lab 2-1

5. When you are finished, close the Design Browser window: Choose File – Quit.

2-6


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Lab 2-2

Using Bindkeys

Lab 2-2

Using Bindkeys

Objective:

To use the bindkeys to impl ement floor planning funct ions.

Using the Bindkey Form

1. Make sure that you are still in the Floorplan view. 2. To display the Bindkey form, choose Options – Set Preference. 3. Select the Design tab, if it is not already selected. 4. To display the Binding Key definition form, click the Binding Key button.

5. To sort all the actions alphabetically by the action names, click Action. 6. To sort the bindkeys alphabetically by the binding key names, click Key.

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2-7

Using Bindkeys

Lab 2-2

7. Redefine the zoomIn key as P.

8. Click OK. 9. Test that the key has been redefined. 10. Reset the zoomIn key back to z. 11. In the Preferences form, click Cancel.

Using Bindkeys 1. To zoom out, Press Shift-z. 2. To pan right, press the right arrow keys. 3. Click the green hard macro RAM_256x16_INST. It is the first macro to the right of the core area. The blue flight lines display connections between the block and the module guide that it connects to.

2-8


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Lab 2-2

Using Bindkeys

4. Double-click RAM_256X16_INST. The Attribute Editor appears 5. Check the orientation of the macro. What is the orientation of the hard block?

Answer: ________________________ _________________________ _ 6. Close the Attribute Editor form. 7. Click the Move button and move the RAM inside the core area of the design. 8. Click left to place the RAM inside the core area. 9. To display the Flip/Rotate Selected Instances form, p ress r. 10. Select R90. Click OK. 11. To exit the move mode and to be in the selection mode, press a. 12. Select DTMF_INST, the large pink module on the left of the core area. 13. To ungroup the DTMF_INST module, module, press Shift-g once.

You are still in select mode. 14. Select a pink module.

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2-9

Using Bindkeys

Lab 2-2

15. Hold the Shift key and select another module. 16. Release the Shift key after selecting another module. 17. Click the Move button. Move the two modules into the core area. 18. Click left to place the modules.

2-10


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Lab 2-3

Tearing Off Menus

Lab 2-3

Teari Tearing ng Off Menus

Objective:

To use the tear-off tear-off menu feature feature when you have have to repeat repeat tasks. tasks.

1. Choose Floorplan. 2. To detach the menu from the main task bar, click the dashed line above the menu list.

3. Place the detached menu in a convenient location on your desktop.

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2-11

Clearing the Floorplan

Lab 2-4

Lab 2-4

Clearin g the Floorplan

Objective:

To clear floor planning objects from a floor plan to impro ve an existing floor plan or create a new one.

1. To display the Clear Floorplan form, on the Floorplan menu, choose Clear Floorplan. 2. Select All Floorplan Objects.

3. Click OK. The module guides and the hard macro that were placed in the core area are unplaced. You can clear all floorplan objects or a subset of floorplan objects.

2-12


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Lab 2-5

Initializing the Floorplan

Lab 2-5

Initi alizing the Floorplan

Objective:

To set the aspect ratio and explore the hierarchy.

1. Choose Specify Floorplan. The Specify Floorplan form appears.

2. Enter 100 for Core to Left, Core to Right, Core to Top and Core to Bottom values. 3. To display more information about the options, on the Specify Floorplan form, click Help. 4. To initialize the floorplan, click OK. 5. To measure the distance between the core area and the I/O boundary, click the Ruler icon or press k.

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2-13

Initializing the Floorplan

Lab 2-5

6. To delete the ruler, click the Clear All ruler icon or press Shift-k.

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Lab 2-6

Customizing the Menus

Lab 2-6

Custom izing the Menus

Objective:

To create a menu item and associated commands.

To add and delete menu items, use the commands uiAdd and uiDelete. 1. In the csh window where you started the tool, run the following command: ui Add expMenu - t ype menu - l abel NewMenu - i n mai n Tip:

You can copy and paste all the commands in this lab section from the TCL script menuAdd.tcl, which has been provided in the work directory.

2. Notice that the new menu NewMenu appears in the upper-right corner of the main menu. You might have to expand the design window to see the newly created menu. 3. To add a subcommand under NewMenu, enter the following command: ui Add expCmd - t ype command -l abel "New command. . . " \ - command [l i st put s "execut e my command"] - i n expMenu

4. To identify the existing menu where you add a new menu item, enter the following command: set vMenu [ ui Fi nd mai n - t ype menu - l abel \ " Ver i f y" ]

5. To add New Verify to the Verify menu, run the following command: ui Add expVer i f y - t ype command \ - l abel "New Ver i f y. . . " - command [ l i st put s \ " New Ver i f y"] - i n $vMenu

Notice that a new menu item appears under the Verify menu. 6. To add a new toolbar, enter the following: ui Add expTool bar - t ype t ool bar - i n mai n - l abel \ “New Tool bar " - newl i ne t r ue

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2-15

Customizing the Menus

Lab 2-6

7. To add the new tool button my toolbutton on the New toolbar, enter the following: ui Add expTool but t on - t ype t ool but t on - i n expTool bar \ - l abel "new t ool but t on" - t ool t i p "new t ool but t on" \ - i con [ f i l e j oi n . / \ l ayout - pl ace- i n- schemat i c. png] \ - command [ l i st put s “New t ool but t on …”]

8. To delete NewMenu (which you created in a previous step), enter this command: ui Del et e expMenu

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Lab 2-7

Checking the Design

Lab 2-7

Checking the Design

Objective:

To determine if there is missing or incor rect infor mation in the libraries or in the netlist.

In this lab, you check the design files and identify the problems to fix. 1. To check the design, run the following command: checkDesi gn - net l i st

The checkDesign command will check the following: 

The netlist after the design has been loaded



The physical library before floorplanning



Power and ground connections before routing and extraction



The legal placement of cells





Timing libraries before any timing-related operations are run such as timing-driven placement and routing, timing optimization, clock-tree synthesis, and static timing analysis Tie-high and/or tie-low connections before routing and extraction

2. View the checkDesign/DTMF_CHIP.main.htm.ascii file. How many output floating nets(nets without fanout) are in the design?

You can find the answer by viewing the checkDesign/DTMF_CHIP.main.htm file with Mozilla or a browser of your choice and looking for the string Output Floating Nets. Alternatively, you can check for the string Output Floating nets in the checkDesign/DTMF_CHIP.main.htm.ascii file. Answer: _____________ Which cells are marked “Don’t Use”?

Answer: _____________ 3. At the prompt, enter: hel p checkDesi gn

Running help before commands will list the all the available options for the command.

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2-17

Floorplanning a Design

Lab 2-8

Lab 2-8

Floorplanni ng a Design

Objective:

To floor plan and explore manual floor planning icon s.

Floorplanning This section introduces you to the floorplanning ic ons in the Tools area. 1. To display the functionality of each icon, position your cursor over each one in the Tools area.

2. To pan left in the design window, click the left arrow key. 3. To set the percentage to pan, choose Options – Set Preference. 4. Click the Display tab. 5. Set Percentage of Window to Pan to 50.

6. Click OK. Do you see a difference in panning after you set the percentag e to 50?

7. To pan slowly to the left or right, pressing Ctrl while moving the scroll wheel forwards or backwards. 8. To pan slowly up or down, press Shift while moving the scroll wheel forwards or backwards. 9. Select a pink module guide.

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Lab 2-8


10. To move down the hierarchy, click Ungroup once. 11. Click the Move button. Move the selected pink module guide into the core design area. If you do not want to display these blue flight lines, click the All Colors button.

The Color Preferences form is displayed. 12. Under the View-Only tab, deselect Flight Line.

13. Close the Color Preferences form. 14. Click the Cut Rectilinear icon. 15. Grab an edge or corner of the selected module guide with the left mouse button and draw a box to represent the cutout area. 16. Click, again. The resulting rectangle is the cutout area of the originally rectangular-shaped guide.

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2-19


Lab 2-8

Notice that the TU number changes. The TU value is the target utilization percentage for a given module area.

17. Click the Select icon. What is the binding key that you can use instead? (The binding key is associated with the selectMode action in the Binding Key form.)

Answer: ________________________ 18. To create placement blockage, click the corresponding icon. Click the left mouse button to create the blockage. Make sure that the blockage that you create does not overlap a module. 19. Select the placement blockage that you created. To view the properties, press q. What type of placement blockage is it?

Answer: ________________________ 20. Close the Attribute Editor. 21. To determine the difference among hard, soft, and partial blockage, see the Encounter documentation.

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6/18/12

Lab 2-8


Relative Floorplannin g In this section, you use the Relative Floorplan tool to place blocks in the core area. 1. Click All Colors and, under the View Only tab, make sure that Instance Pin is selected.

2. Select the DTMF_INST/ARB_INST/ROM_512x16_0_INST hardmacro. 3. From the detached menu, choose Relative Floorplan – Edit Constraint. If you’ve closed the floorplan form, choose Floorplan – Relative Floorplan – Edit Constraint. 4. Make sure that the DTMF_INST/ARB_INST/ROM_512x16_0_INST block is in the Object field. If the Object field is empty, in the Relative Floorplan form, click the Get Selected button. 5. Click Relative to Object. To select bottom core boundary, click the arrow. 6. In the Relation field, select Above.

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Lab 2-8

7. In the Align by field, select Left Side.

8. Click Apply. 9. To place the DTMF_INST/PLLCLK_INST block relative to the bottom of the core boundary, select the block. 10. Click get selected. 11. Select Bottom_Core_Boundary for the Relative to Object parameter. 12. For Relation, click Above. 13. For Space, enter 20.

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Lab 2-8


14. In the Align by field, enter -20. Select Right Side.

15. Click Apply. 16. Click Save. 17. Enter dtmf_relfp.tcl. Relative floorplanning commands are saved in the specified Tcl file. 18. View the saved Tcl script. Notice that the saved parameters correspond to the settings that you specified in the forms earlier. 19. Click Cancel.

Auto mat ic Floor plannin g Syn thesi s f or Bloc k Placement You can place the blocks in your design before placing the standard cells by running automatic floorplan synthesis. 1. To undo the floorplanning that you have finished in this lab, choose Clear Floorplan in the detached menu.

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Lab 2-8

2. Select All Floorplan Objects. Click OK. 3. In the Floorplan menu, select Automatic Floorplan – Plan Design. 4. Click the setPlanDesignMode tab. 5. Select Keep Guide. 6. Click Apply. 7. Notice the placement of the macros. 8. Now, in addition to Keep Guide, select Group Hard Macro. Click OK. 9. Notice the placement of the macros with this combination of options. Typically, you run block placement with various combinations of options to arrive at a desired placement to save and use as the starting point for the next implementation steps. The blocks (hardmacros) and the guides that contain the blocks are placed in the core area automatically. The guides that do not contain hardmacros remain outside the core area.

Adding a Block Halo 1. Select the PLL block. If it is too close to another macro or the edge of the core area, move it to a different location so that there is enough space around it to add a halo. 2. To add a placement blockage around the block: a. Choose Edit Floorplan – Edit Halo. b. Click Selected Blocks/Pads. c. Select Placement Halo. d. For top, bottom, left, and right dimensions of the halo. enter 5 um. e. Click OK. 3. To view the halo, zoom in to the area where the block is placed.

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Lab 2-8


4. To create a routing blockage, click the corresponding icon with the left mouse button to create the blockage in a corner of the core area. Routing blockages are added to the design to alleviate areas of possible routing congestion. 5. Select the created routing blockage. To view the properties, press q. Which layer is blocked?

Answer: ________________ 6. Close the Attribute Editor form. 7. To save the floorplan in the FP format, choose File – Save – Floorplan. For the filename, enter dtmf_fp.fp. 8. Click Save. 9. View the saved floorplan file.

10. Notice that the routing blockage is saved as the RouteBlockages attribute. 11. Create a placement blockage in any area of the core. A partial placement blockage can alleviate congestion by spreading components farther apart during placement. 12. To view its properties, select the blockage. Press q. 13. Change the Type cyclic field from Hard to Partial.

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Lab 2-8

14. In the cyclic field, change the placement percentage to 25%. 15. Click OK.

Power Planning 1. Before running power planning, clear the floorplan by choosing Floorplan – Clear Floorplan. 2. Clear all floorplan objects. 3. To place the blocks, choose Floorplan – Automatic Floorplan – Plan Design. 4. Click the setPlanDesignMode tab. 5. Deselect Group Hard Macro. 6. Select Boundary Place options. 7. Deselect Keep Guide. 8. Click OK. The resulting block placement looks like the following:

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Lab 2-8


9. Choose Power-Power Planning – Add Ring. The Add Rings form is displayed.

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Lab 2-8

10. To select the VDD and VSS nets, click the icon in the Net(s) field. The Net Selection form is displayed. 11. In the Possible Nets pane, press Shift and VDD and VSS. 12. Click Add. The selected nets appear in the Chosen Nets pane. 13. Click OK. 14. Make sure that the Net(s) field contains VDD and VSS. 15. Click Core ring(s) contouring. 16. Select Around core boundary. 17. In the Ring Configuration field, make sure that METAL5 H layer is selected for Top and Bottom. 18. Make sure that a width of 8 and a spacing of 1 are set. 19. Use METAL6 V as the layer for left and right. Select a width of 8 and a spacing of 1. 20. Under Offset, in all the fields, select Specify and enter 1. 21. To generate the power rings, click Apply. Next, you create the rings for the PLL block. It is the only block that does not have a selfcontained ring. 22. In the design window, select the PLL block. 23. In the same form, in the Ring Type section, select Block ring(s) around. 24. Select Each selected block and/or group of core rows.

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Lab 2-8


25. Click the Advanced tab.

26. Configure the segments as shown above so that the power rings around the PLL use the edges of the core rings. 27. Maintaining all other default settings, click OK.

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Lab 2-8

The power plan looks like this.

28. Choose Power-Power Planning – Add Stripe. The Add Stripes form appears.

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Lab 2-8


29. In the form, do the following: a. Make sure that the Net(s) field contains VDD and VSS. b. In the cyclic field, select Metal6. c. Select Vertical, if it is not already selected. d. Set Width to 8. e. Set Spacing to 1. c. Set Set-to-set distance to 100. f. For the Relative from Core Area, or selected area, value, enter 100 for both X from left and X from right. g. Click OK. Notice the power stripes and the vias connecting the rings to the stripes are created.

Preplacing a Cell with the Design Browser 1. Detach the Tools menu. 2. Select Design Browser in the Tools menu. 3. In the Find field, enter the instance name: DTMF_I NST/ DI GI T_REG_I NST/ di gi t _out _r eg_3

4. Press Enter. A standard cell of cell type SDFFSHQX1 is displayed

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Lab 2-8

5. In the Design Browser form, select the instance. To open the Attribute form for the instance click the Attribute Editor icon. The Attribute Editor for this instance is displayed.

6. Do the following: a. In the Attribute Editor in the Location section, click the mouse icon b. Move the mouse pointer in the core design area. The pointer changes to a crosshair. c. Click a point in the core area of the design to preplace the instance. In the form, the coordinates in the Location field are populated by the coordinates where you click. d. In the Attribute Editor, change the Status field to Placed. Click OK. e. Select Physical View, if it is not already the current view.

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Lab 2-8


f. Make sure that, under the All Colors menu, Instance and Std. Cell are set to Visible.

Can you see the preplaced standard cell?

Answer: _________________________ 7. To close the Design Browser, choose File – Quit. Note:

You can use this method to preplace a module, block or standard cell with the Design Browser.

Creating Followp in Routing w ith Special Route 1. Before creating followpin routing, associate the global VDD and VSS nets names to the standard cell pin names by entering the following commands: gl obal Net Connect VDD - t ype pgpi n - pi n VDD - i nst * gl obal Net Connect VSS - t ype pgpi n - pi n VSS - i nst *

2. Cut the rows around the blocks by selecting Floorplan – Row – Cut Core Rows. The Cut Core Rows form is displayed. 3. To select all the blocks in the design, press Shift and click one block. Then select all other blocks. 4. Make sure that in the bottom-right pane, SelNum is 4 to reflect the number of selected objects.

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Lab 2-8

5. In the Cut Core Rows form, select Selected Objects.

6. Select Add Gap on each side. 7. In the Left and Right fields, enter 22. 8. For the Top and Bottom fields, enter 0. 9. Click OK. 10. Choose Route – Special Route. The SRoute form appears.

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Lab 2-8


11. To populate the field with VDD and VSS , click the icon next to the Net(s) field. 12. Click Add to add the nets to the Chosen Nets field and click OK. 13. Deselect all options except Follow Pins. 14. For Layer Change Control, select Metal 6 for Top Layer and Metal 1 for Bottom Layer. 15. Make sure that Allow Jogging and Allow Layer Control are selected. 16. Click OK. The power router takes a few minutes to finish. 17. Choose Tools – Violation Browser. 18. Click Clear Violation. 19. Click Close. 20. In the Physical view, zoom in to the followpin routes. 21. Notice that the power routes have been connected to the power planned targets with relevant vias.

Clearing Floor plan Objects 1. Select the Floorplan View icon. 2. To remove the objects from your current floorplan view, choose Floorplan – Clear Floorplan. 3. Select All Floorplan Objects. Click OK.

Saving the Session 1. Keep the session open. To save the session, choosing File – Save Design. 2. Select Encounter.

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Lab 2-8

3. Enter this filename: f l oor pl an. enc

4. Click OK. 5. Close the session.

Summary In this lab, you read in a gate-level netlist, floorplanned, and experimented with the To ols menu.

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Module 3:

Placement and Trial Route

Lab 3-1

Running Placement

Lab 3-1

Running Placement

Objecti ve:

To read in a floor plan file and place the standard cells in the design.

1. To start the Encounter ® Digital Implementation software, enter: encount er

2. Choose File – Import Design. Load the dtmf.globals file. 3. To load a floorplan file: a. Choose File – Load – Floorplan. b. Select dtmf.fp. c. Click Open. d. Click OK. 4. Choose Options – Set Mode – Mode Setup. 5. In the List of Modes section, click Placement. The Placement Mode pane is displayed.

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3-1

Running Placement

Lab 3-1

6. In the Placement Mode pane: a. Make sure that Congestion Effort is set to Auto. b. Select Run Timing Driven Placement, if it is not already selected. c. Click OK. 7. Load the scan DEF file by running the following command: def I n scan_i nput . def

Alternatively, you can specify the two scan chains in the design by entering the following: speci f yScanChai n scan1 \ - st ar t {I OPADS_I NST/ Pscani n1i p/ C} \ - st op {I OPADS_I NST/ Pscanout 1op/ I } speci f yScanChai n scan2 \ - st ar t {I OPADS_I NST/ Pscani n2i p/ C} \ - st op {I OPADS_I NST/ Pscanout 2op/ I } Note:

Instead of entering the specifyScanChain commands, you can source the scan.tcl file in the work directory.

8. Choose Place – Place Standard Cell. The Place form is displayed.

9. Select the Run Full Placement option, if it is not already selected. 10. Select the Include Pre-Place Optimization, if it is not already selected.

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Lab 3-1

Running Placement

11. Accept the default options. To run placement, click OK. The placement takes a few minutes to finish. Notice that the status of the design on the lower-right corner has changed. After the placement run completes, what is the status of the design that is displayed?

Answer: _____________________ This field is a convenient way to check where you are in the flow. 12. In a separate xterm window, view the log file for this session. What were the initial and final wirelengths of scan1 and scan2 as a result of reordering?

Answer: ___________________________________ 13. To save the scan DEF files, enter the following: def Out BySect i on –noNet s –noComps – scanChai ns sc an. def

14. To display the Physical view, click the Physical View button. 15. Display the scan chains by selecting Place– Display– Display Scan Chain. a. Select Selected Scan Group. b. Enter scan1 in the field. c. Click Apply. You might need to press F12 in order to see the chain clearly. 16. Under All Colors, make sure that Std. Cell and Instance are set to Visible. 17. Zoom in to see the standard cell placements. Notice that in addition to cell placement, Trial Route has been run on the design. 18. To see the congestion display better, turn off the visibility of the nets.

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3-3

Running Placement

Lab 3-1

19. Click the All Colors button. 20. Click the View Only tab.

21. Select the Vertical Congest, Horizontal Congest, Congestion, and Congestion Label options, if they are not already selected. 22. Zoom in to see the congestion. Is the congestion mainly in the vertical or in the horizontal direction?

Answer: ____________________ 23. Choose Place – Display – Display Scan Chain. The Display Scan Connections form is displayed. 24. With defaults selected, click OK. Notice that the scan chain paths are selected (highlighted). 25. To clear the selection, choose Place – Display – Clear Scan Display. The Clear Scan Display form is displayed. 26. With defaults selected, click OK. 3-4


06/18/12

Lab 3-1

Running Placement

27. Zoom in to see the placement of the cells. 28. To save the design, choosing File – Save Design. 29. Select Encounter in the Save Design form. 30. Enter this filename: pl acement . enc

31. Click OK.

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3-5

Running a Trial Route

Lab 3-2

Lab 3-2

Runnin g a Trial Route

Objective:

To restrict the layers for Trial Router and to analyze routi ng congestion

1. To run a trial route, choose Route – Trial Route.

2. Make sure that the max. route layer is set to 4. (Even though there are six routing layers for this technology, for this lab, you restrict Trial Route to use only four layers.) 3. To run Trial Route with Medium (default) effort, click OK. Use all other default options. Notice the diamond and multicolored congestion shapes that are displayed in the Design window. These are areas of congestion.

Viewing Routin g Congestion 1. Click the All Colors button. The Color Preferences form is displayed.

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Lab 3-2


2. Click the View Only tab and then: a. Deselect the net visibility.

b. Select Horizontal Congest and Vertical Congest, if not already selected. c. To display the Vertical Congest Color Selection form, in the Vertical Congest area, click the square shape next to the check box. The colors on this form map to the congestion colors that result from running Trial Route.

d. Click Close.

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3-7


Lab 3-2

3. In the Physical view, zoom in to a red diamond shape. These diamond shapes are areas with routing congestion problems. Rectangles within the diamond shapes are displayed. Also displayed are horizontal or vertical congestion with n umbers: V= # / # or H = # / # . Without zooming in, the congestion numbers might be difficult to see. The V and H apply to vertical and horizontal routing tracks. The first number indicates the required tracks; the second number ind icates the total available tracks. The degree of congestion is displayed with different color coding. The colors in increasing order of congestion are blue, green, yellow, red, magenta, grey, and white. These diamond-shaped congestion locators represent an average in the area. By default, an area is identified as being congested even if the number of available tracks equals the number of required tracks. You can change this behavior with the Preferences form. 4. To turn off the trial route markers, click All Colors. 5. Click the View Only tab. 6. Deselect Congestion, Congestion Label, Horizontal Congest, and Vertical Congest. 7. Close the Color Preferences form.

Saving the Design 1. To save the session, choose File – Save Design. 2. Select Encounter. 3. In the file name field, enter routed.enc. Click OK. To restore your work in a future session, choose File – Restore Design. For the filename, enter routed.enc.

Viewing a Design Aft er a Trial Route 1. Make sure that you are in the Physical view. 2. Set Net visibility to on, if it is off.

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06/18/12

Lab 3-2


3. Zoom in to see the routes. 4. Deselect Std. Cell selectibility. 5. Select a net. 6. To dim the background so that you can see the net better, press F12. 7. To display the Attribute Editor and view its prope rties, double-click the net.

2

What is the name of the net?

Answer: ______________________ Which layer is the selected net on?

Answer: ______________________ 8. Close the Attribute Editor. 9. To deselect the net, click in any empty space. 10. To reset the visibility, press F12 twice. 11. Choose Tools – Design Browser. 12. Change the Find cyclic field from Instance to Net. 13. In the Design Browser, enter the net name: DTMF_ I NST/ TDSP_CORE_I NST/ MPY_32_I NST/ n_334

14. Press Return. 15. In the Design Browser, select the net. 16. Click the Select button in the Design Browser. This choice selects the net in the Physical view. 17. To verify that the net is selected, look at the SelNum value in the lower-right corner of the design window. 18. To see this net, in the Design Browser form, click the Zoom Selected button. You might have to zoom in further to this area to see this net. 06/18/12


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Lab 3-2

19. To display the net better, dim the background and press F12. To return to the original display, press F12 again. 20. To display all color assignments for the metal layers, click the All Colors button. Click the Wire/Via tab. Note:

By default, Trial Route does not use metal1. To force the trial router to use metal1, enter this command: t r i al Rout e - useM1

21. Save the design. For the file name enter pr.enc. 22. Do not close the software. Note:

If you do close the software, you can restore the design from the pr.enc file that you saved in a previous step.

Summary In this lab, you ran placement and trial routing. You also anal yzed the congestion after trial routing and determined the routability of the design.

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06/18/12

Module 4:

Extraction, Timing Analysis, Optimization, and CTS

Lab 4-1

Extracting RC Data

Lab 4-1

Extracti ng RC Data

Objecti ve:

To extract parasitics based on Trial Route.

Extracting RCs 1. In this lab, you extract RCs (resistance and capacitance). They are a prerequisite for running timing analysis. 2. (Skip the following steps if you did not close Encounter ® Digital Implementation.) If you did close the software before starting this lab, restart the software. a. Restore your design by choosing File – Restore Design. b.

Enter your previously saved pr.enc file.

3. (Skip these steps if you completed the previous lab.) a. If you did not complete the previous lab, change to the work directory. cd wor k

b. Copy the file pr.enc and the directory pr.enc.dat from the saved directory to the work directory. cp - R . . / s aved/ pr . * .

c. Restart the software. d. Restore the pr.enc file. 4. To run extraction, choose Timing – Extract RC. 5. Click OK. Note:

For the purposes of this lab, do not save any files, because the generated files will be very large. The extracted RC information is annotated in the design database.

Notice that the status of the design in the lower-right corner changes from Routed to RC Extracted .

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4-1

Extracting RC Data

Lab 4-1

Calculating Delays For the next step, delays are calculated for the interconnect wires and include instance delays. 1. Choose Timing – Write SDF. 2. Because you have not yet run clock tree synthesis on the design, select Ideal Clock, if it is not selected. 3. Click OK. The command creates a file in SDF format.

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06/18/12

Lab 4-2

Running Timing Analysis and Generating a Slack Report

Lab 4-2

Running Timing Analysi s and Generating a Slack Report

Objecti ve:

To analyze timi ng and displ ay violating paths.

After extracting parasitics, run timing analysis to generate timing reports. 1. Choose Timing – Report Timing. The Timing Analysis form is displayed.

2. Because you have not yet created a clock tree for the design, in the Timing Analysis form, make sure that the Pre-CTS option is selected. Because we are interested in generating reports for setup under worst-case conditions, the Setup option is selected (default). The timing reports are saved to the directory specified in the Output Directory field. Note:

The Pre-Place option considers a zero wire-load model while ignoring highfanout nets. This option is useful to check if there are any errors in your constraints file prior to running placement for the first time.

3. To run timing analysis for setup, click OK. 4. After running the analysis, view the slack repo rt: Choose Timing – Debug Timing. The Display/Generate Timing Report form is displayed.

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4-3

Running Timing Analysis and Generating a Slack Report

Lab 4-2

5. Click OK. The Timing Debug window is displayed. How many failing paths do you have in the design?

Answer: ______________________________________ What is the Worst Negative Slack (WNS) and the Total Negative Slack (TNS)?

Answer: ____________________________________ 6. In the Path section of the Timing Debug window, double-click one of the failing paths.

2

The selected path is highlighted in the Design window. The Timing Path Analyzer with more details in the path is also displayed. 7. To close the Timing Path Analyzer window, click the X in the top-right corner of the window. 8. To close the Timing Debug form, close the window. 9. To run the timing analysis in Multi-Mode Multi-Corner mode run the following commands: al l _set up_anal ysi s_vi ews al l _hol d_anal ysi s_vi ews set _anal ysi s_vi ew - set up { dt mf _vi ew_set up dt mf _vi ew_hol d } \ - hol d { dt mf _vi ew_hol d } t i meDesi gn - pr eCTS –expandedVi ews

What is the WNS for dtmf_view_setup?

Answer: What is the WNS for dtmf_view_hold?

Answer:

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06/18/12

Lab 4-3

Running Timing Optimization

Lab 4-3

Running Timing Optimi zatio n

Objecti ve:

To run timi ng optim ization to clos e timi ng.

Now you can run optimization to fix setup violations. 1. Choose Optimize – Optimize Design. The Optimization form is displayed.

2. Because you have not yet run clock tree synthesis (CTS), make sure that the pre-CTS button is selected. 3. Click the Mode button. The mode setup form is displayed.

a. Make sure that Max Density is set to 0.95. This setting limits the increase in area due to the addition of buffers during optimization. Tip:

Begin with a core utilization that is approximately 5% lower than the final utilization.

b. Click OK.

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4-5

Running Timing Optimization

Lab 4-3

4. To update the Timing Debug screen, choose Timing – Debug Timing. The Timing Debug screen is displayed. 5. Select the File Folder icon next to the Report File(s) parameter.

The Display/Generate Timing Report form is displayed. 6. To regenerate the timing report file and to update the timing display, click OK. Did you close timing with a resulting positive slack?

Answer: ______________ 7. When the optimization has finished, view the log file. Compare the worst post-optimization slack to the pre-optimization slack. 8. Save the design. a. Make sure that you save the file in the work directory and not in the timingReports directory. b. Choose File – Save Design. c. For the filename, enter preCTSopt.enc.

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06/18/12

Lab 4-4

Running Clock Tree Synthesis

Lab 4-4


Objecti ve:

To run cloc k tree synthesis with a clock specifi cation file.

After running placement or pre-CTS optimization, you run clock tree synthesis, which requires a clock specification file. This file specifies target skews, insertion delay, and transition times for the clocks in your design.

Running the Synthesis 1. To generate a CTS spec file from the .sdc file, choose Clock – Synthesize Clock Tree. The Synthesize Clock Tree form is displayed.

2. Click Gen Spec. The Generate Clock Spec form is displayed. 3. Select the first cell in the list that starts with CLK. (You might hav e to scroll.) 4. Press Shift and select all cells that start with CLK . 5. Click the Add button. 6. In the Output Specification File field, enter dtmf_generate.cts. 7. To generate the clock specification file, click OK.

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Lab 4-4

8. In the Synthesize Clock Tree form: a. Make sure that in the clock specification file, the following is specified: dt mf _gener at e. ct s

b. To start clock tree generation, click OK. This step takes a few minutes to run.

Viewing Clock Tree Results 1. Make sure you are in the Physical view. 2. Click the All Colors button to display the Color Preferences form. 3. Click the View-Only tab and unselect Congestion Label, Congestion, Vertical Congest and Horizontal Congest. 4. Click Close in the Color Preferences form. 5. Turn off the visibility of the nets and turn on the visibility of the standard cells.

6. Choose Clock – Display – Display Clock Tree.

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06/18/12

Lab 4-4


7. In the Display Clock Tree form, select Display Clock Tree and All Level.

8. Click Apply. In the Physical View window, the clock tree is selected (highlighted in yellow).

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4-9


Lab 4-4

9. Select Display Clock Phase Delay.

10. Click OK. 11. Zoom in to any area that contains a highlighted area and you see multicolored instances. Note:

These colors represent the different insertions delays for the leaf cells. The color coding is red (most delay), orange, yellow, green, blue-gray, blue, and purple (least delay). The clock segments do not represent the entire clock tree. They represent segments of the tree that are connected to the leaf cells.

12. To clear the display, choose Clock – Display – Clear Clock Tree Display. The clock tree reports are written to the clock_report directory. The clock tree synthesis report is written as ASCII files. 13. View the clock.report file in the clock_report directory. Were all clock constraints met? If not, which constraints were not met?

Answer: ________________________

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06/18/12

Lab 4-4


14. Display the detail routed clocks by first deleting the trial routes in the design by entering the following command: dbDel et eTr i al Rout e

15. Make sure that Std. Cell and Net are visible under All Colors. 16. Choose Clock – Display – Display Clock Tree. a. Select All Clock(s). b. Select Post-Route. c. Select Display Clock Phase Delay. d. Click OK. e. Zoom in to where you see highlighted leaf cells. Notice that there are clock routes in the design. 17. To save the design, choose File – Save Design. Enter this filename: cl ock_t r ee_syn. enc

18. To further analyze the clock tree, choose Clock – Debug Clock Tree. The Clock Initialization form is displayed. 19. Click Add All. 20. Make sure that all the clocks appear in the Selected Clock(s) pane. 21. Select Post-CTS. 22. Click OK.

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4-11


Lab 4-4

The Global Clock Debug Tool is displayed.

The left pane contains details about the clocks in your design. You can expand the levels to display additional information. As you explore the details, notice that some of the clocks seem to be driving too few flip-flops. If this were a real design, you would go back to the SDC file and debug why these clocks are defined in this way and determine if there is an error that must be corrected.

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06/18/12

Lab 4-4


23. Choose Tool – Find Object.

24. In the Object Type field, select Cell. 25. In the Name Pattern field enter CLK*. 26. Select In All Clocks. 27. Click Find. A list of instances that contain the clk string in the clock tree is displayed. 28. In the Global Clock Tree Debug window, choose Clock – Refresh Clock Data. 29. Choose Tool – Find Object. 30. For Object Type, select Min/Max Path. 31. Click Find.

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4-13


Lab 4-4

The Max and Min paths will be displayed in the form.

32. Select the paths one at a time and click the Highlight icon. The right pane contains the root , timescale, and the number of flip-flops. 33. To display the names of the drivers, the leaf cells and their skew and delay values, move your mouse over the objects in the right pane. 34. Explore the clock tree analyst and close it after you are finished. The clock uncertainty value in the dtmf.sdc file includes jitter, skew, and additional margin. Because you have a clock tree now, the actual skew is accounted for by the timing analysis tool. Therefore, you need to reduce the clock uncertainty number and leave in just the jitter value. 35. To change the set_clock_uncertainty value from 0.25 to 0.10, at the Encounter prompt, enter the following commands: set _i nt er act i ve_const r ai nt _modes [ al l _const r ai nt _modes - act i ve] s et _ cl oc k_ unc er t ai nt y 0. 10 - f r om [ al l _ cl oc ks ] - t o [ al l _ cl oc ks ]

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06/18/12

Lab 4-4


36. To run the timing analysis in post-CTS mode, enter the following command: t i meDesi gn - post CTS

Is your slack negative or positive?

Answer: _______________ What is the slack at this point?

Answer: ________________________________ 37. If you have a negative slack, run post-CTS setup optimization. Enter the following: opt Desi gn –post CTS


Answer: _____________ What is the slack in your design? ________________________________

38. To run hold time analysis, enter: t i meDesi gn - post CTS - hol d


Answer: _____________ What is the slack in your design?

Answer: ________________________________ 39. If you have hold violations (negative slack), run optimization for hold. What is the slack after optimization?

Answer: ________________________________ If you have hold violations after running hold optimization, then routing the design might improve or fix the negative slack. In later labs, you will route the design and rerun hold checks to see if you still have violations. 40. Save your design as postCTSopt.enc. 41. Close the session.

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4-15


Lab 4-4

Summary In this lab, you extracted parasitics, ran timing ana lysis, and ran an optimization. After optimization, you ran clock tree synthesis to create a clock tree in your design. You reran timing analysis to check if there are any post-CTS timing violations. When you had violations, you reran optimization to improve timing. For a specific floorplan, you quickly got accurate feedback on the timing of the design.

4-16


06/18/12

Module 5:

Generating Scale Factors for Extraction

Lab 5-1

Extracting and Generating Scale Factors

Lab 5-1

Extracti ng and Generating Scale Factors

Objecti ve:

To extract the RCs in the design with both the sign off and built-in extractors, and generate scale factors.

Generate scaling factors by running the generateRCFactor command on a routed design for better correlation between the built-in extractor and a signoff extractor.

Loading th e Design 1. Verify that your working directory is set to the following: FPR/ wor k

2. To start the software, enter this command in a csh window: encount er

After a short time, the software starts. 3. To load the design that has been detail routed, in the graphical interface, choose File – Restore Design. 4. Select Encounter for Data Type. 5. Specify this file: r out eExt r act . enc

6. To load the design, click OK.

Generatin g Scale Factors with External SPEF File 1. To run the generateRCFactor command to generate the scale factors for preRoute and postRoute scale factors, run the following command: gener at eRCFact or –pr er out e t r ue - post r out e medi um \ - r ef er ence ext er nal Spef - spef MapFi l e spef . map

What are the scale factors that were generated for:

Preroute Cap scale factor ________ Preroute Res scale factor ___________ Postroute Cap scale factor (medium)________ Postroute Res scale factor (medium)___________ 06/18/12


5-1

Extracting and Generating Scale Factors

Lab 5-1

Postroute XCap scale factor (medium)__________ Note:

To set the scale factors, you would modify the create_rc_corner defaults in the dtmf.view file.

2. Close the Encounter software.

Summary In this lab, you 

5-2

Ran the generateRCFactor command to generate scale factors for better correlation of native extraction with signoff extraction.


06/18/12

Module 6:

Power Analysis

Lab 6-1

Running Power Analysis

Lab 6-1 6-1

Running Runnin g Power Analysi s

Objecti Objecti ve:

To run early early power analysis analysis and view the IR drop on power lines.

Starting Starting the Software 1. To change to the working directory, enter: cd FPR/ FPR/ wor k

2. To start the Encounter ® Digital Implementation system, enter: encou encount nt er

The software starts.

Importin g a Design Design 1. To import a gate-level netlist, timing constraints, and libraries: a. Choose File – Import Design to display the Design Import form. b. Load the globals file for this lab by b y clicking Load, selecting the dtmf.globals file, and clicking Open. This file populates the fields in the Design Import window. c. Load the design and libraries by clicking clickin g OK.

Loading a Floorplan 1. To load the dtmf_power.fp file, choose File – Load – Floorplan. 2. Source the power_globals.tcl file with the following: sou sour ce power _gl obal s. t cl

The commands in the script enable the power router to connect the VDD and VSS global nets to the power and ground pins of the components in the design.

Running Placement and Trial Route 1. To run placement, choose Place – Place Standard Cell. Use the default options.

06/18/12


6-1


Lab 6-1

2. Click OK. 3. Select All Colors. 4. Click the View Only tab. Turn off Congestion Label, Horizontal Congest, and Vertical Congest. 5. Choose Route – Trial Route. Use Medium effort.

Extract ing RC Data Data 1. To extract RC, choose Timing – Extract RC. Tip:

To save disk space, you can deselect Save Cap. You don’t need to save this information to a file. It is sufficient that the extraction is done and the status of the design is changed from Routed to to RC Extracted Extracted .

Setting Setting the Power Analysis Mode 1. Choose Power – Power Analysis – Setup. Run Static Power Analysis with the defaults selected.

2. Click OK. 6-2


06/18/12

Lab 6-1


3. Choose Power – Power Analysis – Run. 4. Change Dominant Frequency from 100 to 200 MHz.

5. Click OK. 6. View the DTMF_CHIP.rpt file. file. What is the total internal internal power?

Answer: ___________ What is the total switching switching power?

Answer: ___________ What is the total leakage leakage power?

Answer: ___________ What is the total power? power?

Answer: ___________

Running Early Rail Rail An alysis 1. To display the Physical view, click the Physical View icon. 2. Under All Colors, deselect Net visibility.

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6-3


Lab 6-1

3. To display the Early Analysis form, choose Power – Rail Analysis – Early Rail Analysis.

4. In the Net(s) field, select VDD. 5. In the Net Name Field select VDD. 6. Click Create. The Edit Pad Location Form appears. 7. In the Edit Pad Location Form, in the Net Name field, enter VDD. 8. Click Auto Fetch. 9. Notice that the Pad Location List pane is populated with the names and the coordinates of the pads in the design. 10. Clock Save.

6-4


06/18/12

Lab 6-1


11. For File Name, enter dtmf.vdd.pp. These VDD pad locations, where there are zero IR drops, are reference points defined in the dtmf.vdd.pp file. 12. Click Cancel in the Edit Pad Location form. 13. In the Early Analysis form, in the Pad Location File field, enter dtmf.vdd.pp. 14. Click OK.

Viewing Power Analysis Results After the Power Analysis tool runs, the Power and Rail Analysis Results form is displayed. The filter ranges displayed in the form are or ganized from the highest drop (in red) to the lowest drop (green).

1. Click Apply. What are the primary colors and corresponding ranges of your IR drops?

Answer: ____________________________________________

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6-5


Lab 6-1

2. To change the filter range, for Min, enter 1.59, for Max, enter 1.62.

3. Click the Auto button. 4. To display the IR drop screen, click Apply. The software displays a different IR drop map than before. By narrowing the filter range, you can display a more dramatic IR drop map. Are there any red areas displayed in the main Encounter window?

Answer: __________________________________________ 5. Close the Encounter software.

Summary In this lab, you ran and viewed the power and IR drop analysis of the Encounter software.

6-6


06/18/12

Module 7:

Routing and Optimizing the Design

Lab 7-1

Routing Critical Nets with Shielding and Spacing

Lab 7-1

Routing Critical Nets wit h Shielding and Spacing

Objecti ve:

To specify critic al nets for shielding, and to route and optim ize the design to meet timing and signal integit y.

Certain critical or high-speed nets require shielding or spacing from other nets. In this lab, you specify attributes to shield those nets and to assign the nets used for shielding. You also set up extra spacing for a particular net. Typically, you want to route these nets and shields before routing any other nets.

Loading th e Design 1. Verify that your working directory is set to FPR/ wor k

2. If you did not save your design postCTSopt at the end of an earlier lab, copy a saved design that has been placed and in which the clock tree has been synthesized: cp - R . . / saved/ post CTSopt . enc* .

3. Start the software. 4. Open the postCTSopt.enc design.

Setting Shielded and Spacing Net Att ribut es ®

1. In the csh Encounter window where you started the software, enter this command at the Encounter prompt: s et At t r i but e \ - net DTMF_I NST/ TDSP_CORE_I NST/ r ead_dat a \ - shi el d_net VDD

The actual shielding happens in a later step. 2. To check the attributes that you set for the read_data net, in the same csh window, enter the following: get At t r i but e - net DTMF_I NST/ TDSP_CORE_I NST/ r ead_dat a

Is the read_data net going to be shielded?

Answer: __________________________ If so, with what net will be used for shielding?

Answer: __________________________

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7-1


Lab 7-1

3. To set the net attributes to add space around a critical net (clk ), enter this command: set At t r i but e - net DTMF_I NST/ cl k - pr ef er r ed_ext r a_space 2

If the design is not overly congested, the router adds extra tracks of spacing around the net.

Routing t he Nets You route the shielded net first. After routing the shielded net, you route the spaced net along with the remaining nets. The power nets are connected with default width wires to other prerouted power nets. 1. To select the net for routing, choose Tools – Design Browser. Make sure that you are in the Physical view. The Design Browser form is displayed. a. In the form, change the object from Instance to Net. b. In the field, enter *read_data* and press Return. This will bring up the three nets that fit this criteria.

c. Select the read_data net. d. Click the Select button.

e. Make sure that the SelNum field number is set to 1 in the main design window.

7-2


06/18/12

Lab 7-1


2. To route the selected net, choose Route – NanoRoute – Route. The NanoRoute form is displayed. a. In the Concurrent Routing Features section, turn o n Timing Driven. b. In the Routing Control section, turn on Selected Nets Only. c. Click OK. Make sure that you are still in the Physical view. 3. If the read_data net is selected in the Physical view, zoom in to examine the shielding that is connected to VDD. If the read_data net is not selected, the next step describes how you can select and zoom in. Is the VDD shielding on one side or on both sides of the read_data net?

Answer: __________________________ 4. If the read_data net is not already selected, choose Tools – Design Browser. The Design Browser form is displayed. a. In the form, change the object from Instance to Net. b. In the field, enter *read_data*. c. Press Return. d. In the Design Browser, with the left mouse button, select the net. To select the net in the Encounter window, click the Zoom Selected icon.

e. Zoom in further to examine the net for routing and for shielding that is connected to VDD.

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7-3


Tip:

Lab 7-1

For better visibility, you can dim the background. Press F12.

5. To get back to the original visibility, continue to press F12. 6. To route the remaining nets, choose Route – NanoRoute – Route.

7-4


06/18/12

Lab 7-1


The NanoRoute form is displayed.

a. Before starting the router, in the Routing Control section, turn off Selected Nets Only. b. Make sure that Timing Driven is selected. c. Select SI Driven. d. Select Litho Driven. e. Click Mode in the NanoRoute form. This will bring up the Mode Setup form. f.

In the left-hand pane of the Mode Setup form, make sure that NanoRoute is selected.

g. In the Mode Setup form click the DFM tab. h. Set Concurrent Via Optimization Effort to Medium. i.

Click OK in the Mode Setup Form.

j.

Making sure that Selected Nets Only is turned off , click OK in the NanoRoute form.

7. View the log file for the current session to dete rmine if there were antenna violations that have been fixed during the search-and-repair operation. 8. View the log file to determine the relative percentages of single-cut vias and do ublecut vias. 06/18/12


7-5


Lab 7-1

What is the percentage of single-cut vias in the design?

Answer: What is the percentage of double-cut vias are in the design?

Answer: 9. Select Timing – Report Timing to run setup timing analysis. 10. Select Setup, Post-Route, and Include SI, and click OK.

Are there any setup violations?

Answer: _________________ 11. Run Hold Timing Analysis in postroute mode and select Include SI.. Are there any hold violations?

Answer:

______________________

12. To save the design, choose File – Save Design. Enter this filename: DTMF_det ai l r out ed. enc

13. Close the Encounter software.

Summary In this lab, you

7-6



Set options to shield and space critical nets in a design.



Routed the critical nets and then the remaining nets.



Routed, timed, and optimzed the entire design. Encounter Digital Implementation (Flat)

06/18/12

Lab 7-1



06/18/12


Ran concurrent SI, timing and via optimization and recorded the results.


7-7

Module 8:

Wire Editing

Lab 8-1

Using the Interactive Wire Editor

Lab 8-1


Objecti ve:

To manually add and modi fy sign al nets.

In this lab, you load a design, set up wire snapping to pins and tracks, and route with nondefault wires. You also route shielded nets and change the width of a signal wire.

Loading th e Design 1. Change the working directory to FPR/ wor k/ EDI T_ROUTE

2. To start the software, in a csh window, enter this command: encount er

3. Load the saved design edit_route.enc.

Locating the Net for Manual Routing 1. To make the Tools menu visible, widen the Encounter window. 2. To find the net to hand-route, choose Tools – Design Browser. 3. In the Design Browser, click the plus sign (+) next to Modules. Expand IOPADS_INST.

4. To see the list of I/O pads, expand Pads. 06/18/12


8-1


Lab 8-1

5. To select the Prefclkip instance, click Prefclkip (PDIDGZ). To view the instance, in the Design Browser window, click the Zoom Selected icon.

The cell is highlighted in red.

8-2


06/18/12

Lab 8-1


The net that you route connects the pin in the lower-right corner of the I/O instance to the PLLCLK_INST block. 6. Make sure that the pins are visible be expanding Cell in the All Colors pane and making sure that the Instance pin visibility is selected.

7. With the left mouse button, draw a box around the Prefclkip pad. 8. With the right mouse button, click and drag to zoom to the point where you can see both the pad pin and the PLL pin for this net. With this view, you can determine an optimal route for the net.

The connectivity of the pin on the pad to the pin on the PLL is displayed. 9. With the right mouse button, click and drag, again, to zoom to an area near the PLL.

06/18/12


8-3


Lab 8-1

Using the Wire Editor

Bindkeys for the Wire Editor

Bindkey

Description

A

Starts the Add Wire mode. The cursor turns into a pencil. Left-click to add wires if the Nets field has a net in it.

d

Opens the Select/Delete route form.

e

Brings up Edit Route form.

n

Selects the Next Auto Query object (in Query mode only).

p

Selects the Previous Auto Query object (in Quer y mode only).

S

Selects the current Auto Query object and seeds the Nets tab's Nets field and the Route tab's Layer and Width fields in the Edit Route form (in Query mode only).

u

Changes wire to next higher layer (in Add Wire mode).

d

Changes wire to next lower layer (in Add Wire mode).

Control-w

Deletes the last wire segment created (Query mode only).

R

Enters non-connectivity move mode.

N (next) or P Displays or replaces a via that has the same LEF rule as (previous) the selected via Click

Ends the current wire segment.

Double-click Enters current point and stops wire creation.

Note:

8-4

For a list of all bindkeys and how to add bindkeys, choose Options – Set Preferences, and then click Binding Key. Encounter Digital Implementation (Flat)

06/18/12

Lab 8-1


1. Make sure that you are still in the Physical view. 2. Zoom in to the pin that you are routing. 3. To display the Edit Route form, with the Encounter window active, press e. 4. To set wire snapping options, click the Snap tab. 5. Turn off Snap to Track (Regular). 6. Turn on Snap to Pin. Set Alignment to Center.

7. On the Edit Route form, click the Nets tab. 8. To set the selection of objects to 0, click an area where there is empty space. 9. To turn on the autoquery function, at the bottom of the Encounter graphical interface, click the Q button.

To add the net name in the Nets field, use the autoquery feature. 10. Make sure that the Encounter window is the active window. Move the pointer over the refclkI net (connecting to the refclk pin on the PLL block). 11. Press Shift–s to populate the Nets field in the Edit Route form with refclkI .

06/18/12


8-5


Lab 8-1

12. To change the cursor to a pencil for wire editing, make sure that the cursor is in the Encounter window. Press Shift–a or click the Edit Wire icon. 13. On the refclk block pin, click left. The wire snaps to the center of the pin and follows the cursor. The LEF file has the widewire rule defined for layers and vias. To use this rule, on the Nets tab in the Rule field, click the widewire option as shown in the next step. 14. In the Edit Route form, under the Nets tab, change the Rule field from Default to widewire.

A wider wire (defined in the LEF file) comin g from the pin is displayed, but you also see violations. The width of the wire is greater than the pin size and violates the obstructions that surround it. 15. Click the Default rule. Notice that the wire width changes back from wide to the default width. 16. To move the cursor left about half way from the refclk pin to the destination pin, drag the wire. 17. To start drawing the wire on M1, press 1 on the keyboard. 18. To complete this segment of the route, click the left mouse button. 19. Create a vertical wire on M4 by pressing 4. 20. To route with a wide wire in M4, change Rule to widewire.

8-6


06/18/12

Lab 8-1


21. To end the M4 vertical route when the flight line is horizontally even with the I/O pin, click the left mouse button. With this action, you can change to a horizontal routing direction. 22. To change the layer for the horizontal route to M5, press 5. 23. Change the Rule from widewire to default. 24. To finish the route to the I/O pin, double-click the left mouse button near the I/O pin.

2

Because you set the Snap to Pin value to Center, the tool automatically snaps to pin C .

25. To exit wire edit mode and enter select mode, press a. 26. If you want to delete and reroute the net, press d.

06/18/12


8-7


Lab 8-1

Replacing a Via in a Desig n You can replace a selected via with another, provided they both have the same LEF rule. 1. Zoom in to see the area where the stacked vias connecting M1 to M4 were placed on the refclkI net that you routed previously. 2. If it is off, turn on the autoquery function: At the bottom of the Encounter window, click the Q button. 3. To select the via to change, while pressing the left mouse button, draw a box around the vias.

4. To display the Attribute Editor, press q. Confirm that the selected object is the via.

8-8


06/18/12

Lab 8-1


If multiple objects have been selected, to search for the via, click Next.

5. Close the Attribute Editor. 6. Without moving the mouse, use the shift-n (next) or shift-p (previous) bindkey to display a via that has the same LEF rule as the selected via. When you press the bindkey, if a via is available, the display is updated with the new via. However, if another via is not available, then you hear a warning beep when you press the bindkey. This can occur when the following happens: 

Only one via is defined in the LEF file



The currently queried object is not a via



No object is currently queried.

In the LEF file used for this lab, there are two each of the default vias. Note:

The Edit Route form does not provide access to this feature. You can change only one via at a time with the bindkeys.

7. To choose select mode, press a.

06/18/12


8-9


Lab 8-1

Reshaping a Wire To modify a wire after routing or editing, click the Cut Wires and Move Wires icons. 1. Zoom in to an area to see the vertical Metal4 route you completed. 2. Click the Cut Wires icon. 3. Click and drag at two different places on Metal4 where you want to create a jog. Overlapping wire segments that are based on where you made the cuts are displayed.

4. To set the select mod, press a. 5. Select the cut wire segment. 6. Click the Move Wires icon. The cursor changes from an arrow to a circle.

8-10


06/18/12

Lab 8-1


7. To create a jog, click and drag the metal4 segment to where you previously created the cuts. Click where you want to place the segment.

The segment and connecting wires are moved while keeping the route intact.

Forcing t he Width of a Signal Wire In addition to routing a nondefault wire with a wide-wire rule defined in the LEF file, you can also use the Wire Editor to force the width of a wire by making it a special wire. With this procedure you can specify any width for the wire. In this section, assume that you have just learned that the nondefault width used for the refclkI net is too small. You need to make the width of the wire the same as the width of the I/O pad pin. 1. Make sure that you are in Physical view. 2. To delete the refclkI wires, select the segments. 3. To display the Select/Delete/Deselect Routes form, press d. 4. Change Action to Delete.

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8-11


Lab 8-1

5. Set Objects to Selected, if it is not already. 6. Deselect Type, if it is selected. 7. Click Apply. 8. Close the Edit/Delete/Deselect Routes form. 9. To display the Edit Route form, press e. 10. On the Edit Route form, select the Nets tab. 11. To populate the Nets field and select layers for horizontal and vertical routing, on the I/O pad, place the cursor over Pin C and press Shift–s. 12. Turn on Force Special (to allow arbitrary widths). 13. In the Edit Route form, click the Route tab. Set Vertical Layer to M4 and Width to 2.0. 14. Click the Snap tab. Select Snap to Pin and set to Auto, if it is not already. 15. Make sure that the net name in the Nets field is refclkI . 16. To change the cursor to a pencil icon for wire editing, press Shift–a or click the Edit Wire icon. 17. To start the horizontal route, left-click the I/O pin. 18. Left-click to change directions to vertical. Notice that the vertical segment’s width is your specified width for M4. 19. Left-click to change the direction to horizontal. 20. Complete the horizontal route to the PLL block pin with default metal1 widths. Tip:

Select Layer M1 and Default Rule. On the Nets tab, deselect Force Special.

21. When you get to the pin, double-click left to end the route. 8-12


2

06/18/12

Lab 8-1


22. To select the layers for routing, click the numeric keys (1, 2, 3, and so on). 23. When you finish, close the software.


Loaded a design.



Manually routed a net.



Swapped vias.



Modified signal wires.



Forced the width of a wire to a nondefault width.

06/18/12


8-13

Modul od ule e 9:

Verify ri fyin ing g a Design si gn

Lab 9-1

Using the Verify Commands in a Design

Lab 9-1 9-1

Using the Verif Verif y Commands in a Desi Design gn

Objecti Objecti ve:

To use and understand the verify comm ands to check check design design rules.

In this lab, you run different verification options in the Encounter ® system.

Loading th e Design Design 1. Make sure that your working directory is the following: FPR/ FPR/ wor k/ VERI ERI FY

2. To start the software, in an Encounter csh window, enter this command: encou encount nt er

3. To load the design for power routing in the csh Encounter window, choose File – Import Design. 4. At the bottom of the Design Import form, click the Load button. 5. Select the verify.globals file. Click Open. 6. In the Design Import form, click OK. 7. Choose File – Load – DEF. Select the tdsp_core_routed.def file. file. Click Open. Some errors were created in the DEF file for this lab. What errors do you see when you read in the DEF file at this point?

Answer: 8. To see the detailed routes, change your view to Physical View.

Using Verif Verif y Connectivit Connectivit y 1. Choose Verify – Verify Connectivity. The Verify Connectivity form is displayed. 2. Make sure you are in Physical view. Turn on the Geometry Loop option. Click OK.

06/18/12


9-1


Lab 9-1

You can also run this option from the command line. Enter the following: ver i f yConnect i vi t y - geomLoop

Loop problems are reported.

3. To locate the loop, choose Tools – Violation Browser. The Violation Browser form is displayed. 4. If Verify and Connectivity are not expanded, click the plus sign icon (+) next to them to expand the levels in the browser and to display the violating nets.

9-2


06/18/12

Lab 9-1


5. Select the violation on net n_4074. To zoom in to the violation marker, click the net.

6. To see the loop, zoom in to the violation.

7. In the design window, select a loop segment.

06/18/12


9-3


Lab 9-1

8. To remove the loop, press d to display the Select/Delete/Deselect Routes form.

9. In the Action field, select Delete. 10. In the Objects field, select Selected. 11. Click Apply. The selected segment is deleted. 12. Repeat Select and Apply steps until all loop segments are deleted. 13. After you have deleted the loop segments, in the Select/Delete/Deselect form, click Close. 14. Re-run the following command to verify if an y geometry loop remain: ver i f yConnect i vi t y - geomLoop

Using Verify Geometry and the Influence Rule 1. On the Encounter csh command line, enter the following: zoomBox 330 610 360 640

2. Choose Verify – Verify Geometry. a. Click the Specify option. Now you debug errors in the vicinity of the current view area. b. Click the View Area option. Click Apply.

9-4


06/18/12

Lab 9-1


How many Geometry violations are flagged?

Answer: ___________________________ Notice the spacing violations. The corresponding LEF influence spacing rule is: WI DTH 3. 0 WI THI N 0. 90 SPACI NG 0. 90 ;

The influence spacing rule is applied to all shapes within the halo around the wide wire object (within distance 0.9 µm). The halo extends in orthogonal directions only and does not include the corners. Any two shapes in the halo require extra spacing between them (0.9 µm) if the shapes have a combined projected run length onto the wide wire of greater than 3.0 µm.

3. Close the Verify Geometry form and then the Encounter window.


Loaded a design with design rule violations.



Used the Verify flow to find and fix violations.



Observed how the LEF influence spacing rule in is checked in verification.

06/18/12


9-5

Module 10: Running the ECO Flow

Lab 10-1

Loading a Design for ECO Routing

Lab 10-1

Loading a Desig n for ECO Routing

Objecti ve:

To start the Encounter softw are, input the required files, and implement an ECO using a Verilo g file.

Getting Started 1. Make sure that your working directory is set to the following: FPR/ wor k/ ECO

2. Compare the tdsp_core.v and tdsp_core_eco.v files. The tdsp_core.v file is the original netlist. In the tdsp_core_eco.v file, the instances connected to the p_data_out[15] and p_data_out[14] nets have been swapped. To find the nets, search for instances i_5324 and i_5331.

Implementing an ECO in the New Netlist with a Design 1. To start the Encounter ® software, enter the following: encount er ®

2. In the Encounter csh window, run the ecoDesign command to read in the original ® design, read the new Verilog file and implement the ECO: ecoDesi gn t dsp_cor e. enc. dat t dsp_cor e t dsp_cor e_eco. v

The tdsp_core.enc.dat is the design corresponding to the original tdsp_core.v netlist. The tdsp_core_eco.v file contains the required ECO that is implemented. The ecoDesign command routes the changes in the netlist. 3. Write a new DEF file tdsp_core_routed_eco.def . 4. Run the following command to compare the original DEF file tdsp_core.def (which corresponds to the original Verilog netlist) to the current, changed EDI ECO database: ecoCompareNet l i st - def t dsp_cor e. def - out Fi l e ecoFi l e

5. View the ecoFile, and verify the connections have been changed. If this was a production design, you would continue with the postroute flow if you want, including timing and signal integrity anal ysis, repair, metal fill, and verification. 6. To close the software, choose Design – Exit. 06/18/12


10-1

Loading a Design for ECO Routing

Lab 10-1


10-2

Ran an ECO and generated a routed design


06/18/12

Module 11: Database Commands

Lab 11-1

Using the dbGet and dbSet Commands

Lab 11-1

Using the dbGet and

dbSet Commands

Objecti ve:

To repor t and change the EDI database wit h the commands.

dbGet and dbSet

1. Make sure that your working directory is set to the following: FPR/ wor k

2. To start the Encounter ® software, enter the following: encount er

3. From your current directory, restore the previously stored design preCTSopt.enc. Alternatively, you can restore any other saved design. 4. To return the command line options of the command, in the Encounter csh window, enter the following: hel p dbGet

The usage is as follows: Usage: dbGet dbGet [ - p | - ] [-u] [ - r egexp] [-d] { | head | t op | sel ect ed} [ . ] * [ . | . ? | . ?? | . ?h] [ ] [ - hel p]

5. Select head from the attributes that are available at this level. To return the attributes that are available at this level, enter the following: dbGet head. ?

The attributes are as follows: head: head: al l Cel l s cel l EdgeSpaci ngs dbUni t s l ayer s l i bCel l s mf gGr i d obj Type pr ops pt nCel l s r ul es si t es t opCel l s vCel l s vi as

Some useful attributes at this level are dbUnits and mfgGrid .

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6. To report the values, enter the following command : dbGet head. dbUni t s

What is the value that is returned?

Answer: __________________ 7. Enter the following command: dbGet head. mf gGr i d

What is the value that’s returned?

Answer: __________________ 8. To list all the attributes and their values, enter the following: dbGet head. ??

The results might not always be readable tex t, as in this example. 9. To list the layers, enter the following command: dbGet head. l ayer s

However, this command returns a hex representation o f the layer names. 10. To display text, enter the following command: dbGet head. l ayer s. ?

The name attribute displays the text. 11. Enter the following command: dbGet head. l ayer s. name

What does this command return?

Answer: ___________________ 12. To get to the top level of the hierarchy, enter the following command : dbGet t op. ?

This lists all the attributes that you can query. 13. Try out different attributes. Think of examples of how you can use the results in scripts or how to query only the attributes of your design to check, for example, the instances connected to a selected net. 14. In the design window, select ROM_512x16_0_INST .

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15. Enter the following command: dbGet sel ect ed. ?

This command returns the following attributes: i nst : box cel l i nst Ter ms i sDont Touch i sHal oBl ock i sJ t agEl em i sPhysOnl y i sSpar eGat e name obj Type or i ent pSt at us pgCel l Ter ms pgTer mNet s pt

16. To report the size of the halo on the right of the block, enter the following command: dbGet sel ect ed. pHal oRi ght

What is the value that is returned?

Answer: ___________________ 17. To change the size if the halo around the block, enter the following: dbSet sel ect ed. pHal oRi ght 5

18. To view the change, refresh the Encounter design window. 19. To query some of the properties of the selected instances, enter this command: dbGet sel ect ed. pgTer mNet s. ?

20. Explore the attributes and properties that are returned and change them. 21. Save the design as preCTSopt_db.enc. 22. Close the Encounter software.

Summary In this lab, you ran the db commands to report and modify the attributes o f the design and its objects.

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Module 12: Generating and Running the Foundation Flow Scripts

Lab 12-1

Generating and Running the Foundation Flow Scripts

Lab 12-1

Generating and Running the Foundation Flow Script s

Objective:

To start the Encounter platform , generate foundatio ns flow scri pts, and run a design thro ugh a part of the flow.

Getting Started 1. Make sure that your working directory is set to the following: FPR/ wor k/ FF

2. To start the Encounter ® software, enter the following: encount er

Running t he Foundation Flow Wizard 1. To see all pull-down menus, widen the design window. 2. To start the Foundation Flow wizard, choose Flows - Foundation Flow Wizard.

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3. Select Start from Scratch, if it is not already selected. 4. Click Continue. 5. Enter the process node and LEF technology filename as shown:

In this example, the technology part of the LEF file and the physical LEF models for the standard cells and macros are contained in one file. 6. Click Continue. 7. Review the setup and click Continue. This will bring up the Setup your Design Netlist and Floorplan form. 8. To display the form that you use to navigate the directory structure and select the Verilog files, click the File Navigator icon next to the field that will contain the paths and the names of the Verilog netlists.

9. Click the arrows next to Add.

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10. In the right pane, navigate up and in to the verilog directory.

11. Double-click the files dtmf_chip_ak.v and stubs.v. 12. Make sure that the two files are displayed in the left pane.

13. Click Close. 14. Make sure the Verilog field is populated:

15. In the Design Name field, enter DTMF_CHIP.

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Lab 12-1

16. In the Use the floorplan file field, enter ../dtmf.fp.

.

.

17. In the Power Net Name field, specify VDD. 18. In the Ground Net Name field, specify VSS. 19. Click Continue. This will display the Setup Your Clock Tree Synthesis Constraints form.

20. Select Use my clock tree spec file(s). Enter dtmf.cts. 21. Click Continue. When the form is displayed, review your design setup. Make sure that the information that you see is correct 22. Click Continue. The Setup Your Design for Timing-Driven Place an d Route form is displayed. 23. With default selections, click Continue. This will display the Create Timing Library Sets form.

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24. To create a new library set, right-click Library Sets and select New.

The Add Library Set form is displayed. 25. In a separate xterm window, run the following commands: cd wor k vi dt mf . vi ew

To complete the next few steps, you use the parameters specified in the dtmf.view file as a reference 26. In the Add Library Set form, create a new library set called dtmf_libs_max.

27. To populate the fields with the *slow*.lib files and the slow.cdb file, use the navigation icons. To make sure that you select all the files associated with the dtmf_lib_max parameter, refer to the LIB files and CDB file specified for the dtmf_lib_max library set in the dtmf.view file.

28. In the Add Library Set form, click OK.

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Lab 12-1

29. To create another library set, right-click Library Sets and select New. The Add Library Set form is displayed. 30. In the Name field, enter dtmf_libs_min. 31. To populate the fields with the *fast*.lib files and the fast.cdb file, use the navigation icons.

32. Expand the library sets and check your setup.

There are six .lib files in each of the library sets. 33. Click Continue. This will display the Create RC Extraction Corners form. 34. To create a new corner, right-click RC Corners and click New. The Add RC Corner form is displayed. 35. In the Name field, enter dtmf_rc_corner . 12-6


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36. For the Cap Table File field, navigate to or enter the following: . . / . . / capt abl e/ t 018s6ml v. capTbl

37. Do not modify any other fields. Click OK. 38. Expand the dtmf_rc_corner field and make sure that you see the following:

:

39. Click Continue. This will display the Create Delay Corner S ets form. 40. To display the Add Delay Corner form, click the OFF button next to dtmf_libs_max. 41. In the Name field, enter dtmf_corner_max. Click OK. 42. Click the OFF button next to dtmf_libs_min. 43. Enter dtmf_corner_min. Click OK. 44. To display the Create Constraints Mode form, click Continue. 45. Right-click Constraint Modes and select New. 46. In the Name field, enter common. 47. To find the ./dtmf.sdc file, click the Navigate icon.

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Lab 12-1

48. To add to the pane under SDC Constraints Files, double-click the file.

49. Click Close. 50. In the Add Constraint Mode form, click OK. 51. To display the Create Analysis Views form, click Continue. 52. To display the Add Analysis View form, click o ne of the two OFF buttons. 53. If the delay corner in the form is dtmf_corner_max, in the Name field, enter dtmf_view_max. 54. Click Add to setup analysis views. 55. Click Set Active. Click OK. 56. If the delay corner in the form is dtmf_corner_min, In the Name field, enter dtmf_view_min. 57. Click Add to hold analysis views. 58. Click Set Active. Click OK. 59. Click Continue. 60. Review your setup. 12-8


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61. Click Continue. 62. In the interest of time, to accept the defaults in the Setup Your Power form, click Continue. 63. To display the Set Up Tool Specific Options form, click Continue, again. 64. Click Continue, again. 65. To skip selecting the plug-ins, click Continue. 66. Click Done. 67. To save all your inputs to the setup.tcl file, click OK. 68. Click Save. 69. Similarly, save the edi_config.tcl and lp_config.tcl files. 70. To save the scripts that are needed to run the next step, in the EDI window, choose Flows – Create Foundation Flow Template – Save. 71. Click Choose. 72. Exit the Encounter tool.

Generating Foundation Flow Scri pts Now you use the generated setup.tcl to generate Foundation Flow scripts. 1. Run the following command: t cl sh SCRI PTS/ gen_f l ow. t cl - d . al l

Check the setup.tcl file and make sure that the LEF file specification is pointed to ../../lef/all.lef . This command uses the Foundation flow cod e generator to generate the scripts required for implementation, as well as the makefile. 2. View the makefile called Makefile.

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EDIflat_11_1.lab

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