Virtuoso Schematic Composer User Guide

B

Text-to-Symbol Generator

The text-to-symbol generator (TSG) is a Cadence® application program that automatically generates symbol cellviews for schematic composer and subsequent simulation processes.

TSG provides a quick way to generate a symbol from a list of pins in a TSG file.

This appendix describes the TSG file syntax and illustrates the use of various TSG constructs.

■Symbol Shape Generated by TSG on page 597

■TSG Symbol Description File on page 598

■TSG Template File on page 598

■Clock and Negation Indicators on page 599

■Backannotation on page 599

■Simple File Example on page 599

■Complex File Example on page 600

■Extended File Example on page 601

■TSG Symbol Description File Structure on page 603

Basic File Structure on page 603

Data Types on page 605

■Using TSG Constructs on page 607

Cell Definition on page 607

Input Pin on page 608

Output Pin on page 608

I/O Pin on page 608

Symbol Definition on page 609

Virtuoso Schematic Composer User Guide

Text-to-Symbol Generator

Executing TSG on page 620

TSG Processing Order on page 621

Creating Symbols Automatically from a Schematic on page 621

Virtuoso Schematic Composer User Guide

Text-to-Symbol Generator

Symbol Shape Generated by TSG

All symbols generated by TSG are rectangular in shape. The default origin of a symbol is located at the upper left pin terminal. The following symbol was created by TSG.

Virtuoso Schematic Composer User Guide

Text-to-Symbol Generator

An Instance

An instance of the symbol shown above when placed in a schematic

U2

TSGFIG

TSG Symbol Description File

The TSG symbol description file is the primary input file that controls the symbol to be generated by TSG. This ASCII file is built using the constructs detailed in this appendix. You can create a very simple file containing only the cell name and the pin names, or you can add constructs to enhance the symbol description.

Defaults and error checking are built-in features of TSG. TSG has extensive error checking and error handling capabilities. It checks for syntax, variable-type, and logical errors in the TSG symbol description file. Depending on the severity of a detected error, TSG either exits the generation of the current symbol or displays an error message and continues processing.

TSG Template File

The TSG template file is a secondary input file that specifies default controls for symbols to be generated by TSG. The TSG template file uses the same format as the TSG symbol description file. Within this file, you can configure symbol labels, properties, and characteristics such as pin spacing, stub length, and origin placement.