Running Assura DRC from AWRDE

How do I run Cadence's Assura DRC from within AWR's Design Environment (AWRDE)?

Assura DRC is supported in AWRDE v7.5 or higher. Some of the important features are support for secure shell (ssh), simple user setup, area DRC,and ability to mark errors as Checked or False.

The Assura integration requires an optional ASR-100 feature in the License File . To determine whether or not you have this feature, perform the following steps from within the AWRDE:

Select File > License > Feature Setup

You must have ASR-100 in Optional Features for the Assura integration to work properly. If you do not have this feature, contact your local AWR Sales representative for assistance.

The purpose of this article is to show users the how to run Assura DRC from within the AWRDE. It is expected that Assura DRC is installed and running on a UNIX or Linux computer prior to integrating with the AWRDE. How to set up Assura DRC is beyond the scope of this article. Contact your local Cadence representative for help in getting Assura DRC running.

Assura DRC runs on a either UNIX or Linux computer. In this article, "Linux" will be used generically to refer to either Unix or Linux. We support both remote shell (rsh) and secure shell (ssh) as communication protocols between the PC running AWRDE and the Linux machine running Assura DRC.

For using rsh, AWRDE uses the Windows built-in rsh functionality. To use ssh, you will need a ssh, telnet, and rlogin client called PuTTY .

The AWRDE setup for using rsh or ssh is done by selecting Help > Show Files/Directories and adding the following statements to the user.ini file.

For rsh:

                                [ASSURA_DRC] 
                                Machine=name_of_Linux_machine_where_Assura_DRC_runs 
                        

For ssh:

                                [ASSURA_DRC] 
                                Machine=name_of_Linux_machine_where_Assura_DRC_runs 
                                NetClient=PuTTY
                                Password=-i point_to_PuTTY_generated_private_key_file 
                        

OR

                        Password=-pw type_user's_Linux_password 
                

Note: If using the "-pw" option, the user's password will be plainly visible to anyone viewing user.ini . Because of this, users might prefer the "-i" key approach, where a private/public key pair (both of which are encrypted) is generated using PuTTYgen , which is PuTTY key generator. For more information on creating and using keys, the user is referred to Chapter 8 of PuTTY's User Manual which covers using public keys for SSH authentication.

After performing these steps, save and close your user.ini and text editor, and then close the Directories window.

In addition, if using ssh, the path to putty.exe needs to be specified in the Windows Path environment variable by right-clicking on My Computer, going to Properties > Advanced > Environment Variables, and adding the path to putty.exe . The default location is C:\Program Files\PuTTY .

For version 9.0 and later, the following directions apply:

• Open the layout you would like to DRC and select Verify > Design Rule Check .

• Click Configure .

• Browse to Rule Deck.

• Select Assura as Engines and click OK

• Click Run DRC

At this point, AWRDE will create a GDS of the layout, copy the GDS file and rule file to the Linux computer, do the Assura DRC run, and bring back the results of the DRC run. The results of the DRC run will display as either "No DRC errors" or the errors will be highlighted. The user can highlight errors in groups or 1-by-1 and fix them, mark them as Checked, or mark them as False.

In addition, errors can be saved for later review. With your layout open, select Verify > Save DRC Errors. The saved errors can be loaded by selecting Verify > Load DRC Errors.

Area DRC is also available to the user. This can be enabled by selecting Verify > DRC Check Area, drawing a window around the area to be checked, clicking DRC check area in the DRC window, followed by Run DRC.

Troubleshooting:

If DRC did not complete properly, an error transcript log will appear. Before looking in detail into the log, check that the PC and Linux computer are connected using the following steps:

For rsh: Open a DOS window by selecting Start > Run and type cmd in the box that appear. At the DOS prompt, type

                        rsh name_of_Linux_machine_where_Assura_DRC_runs ls 
                

This should return a listing of the files the user has in his Linux HOME directory. If the command errors or times out, the PC is not connected to the Linux computer. Sometimes users have seen rsh connectivity problems due to the Windows Firewall, so you may want to test this having the Firewall turned off. To do this, select Start > Control Panel > Security Center > Windows Firewall and in the General tab turn Off the Firewall. At this point if rsh is not connecting, your IT department might need to help resolve the issue. If rsh is working, the PC is connected to the Linux machine, so you can look into the DRC error transcript log.

For ssh: Test PC/Linux connectivity using PuTTY:

• If using the "-i" keys approach: In PuTTY , in Session category, enter Host Name (which is the name_of_Linux_machine_where_Assura_DRC_runs in this example) and select SSH as Protocol. In Connection > SSH > Auth category, point to the private key specified in the "-i" option click Open. If connection is unsuccessful, the error messages should give an idea of what the problem is. Depending on the problem, your IT department might need to help resolve the issue.

• If using the "-pw" password approach: In PuTTY , in Session category, enter Host Name (which is the name_of_Linux_machine_where_Assura_DRC_runs in this example) and SSH as Protocol. Click Open. If this doesn't connect, your IT department might need to help resolve the issue.

If proper connection is made, a window asking your username and password should appear. If proper connection is made in either of the above cases, this means ssh is properly connecting the PC and Linux computer, so you can view the DRC error transcript log.