Technology File

The technology file tells Xic all it knows about the layers and display attributes, as well as being a general source of initialization information. The name of the file is ``xic_tech'', and an extension .xxx can be added to the name, so that if Xic is started with the -Txxx option, the technology file with the extension will be used. For example, ``xic -Ttrw'' would cause Xic to read xic_tech.trw.

It is legitimate to start Xic without reading a technology file, by using ``xic -T''. In this case, new layers will be assigned as needed as cells are read in. This can be useful for examining an undocumented GDSII file, for example. Once the layout has been read in, new colors and fill styles can be assigned, and the Save Tech command in the Attributes Menu used to dump an appropriate technology file for the next time.

The technology file is expected to be found along the library search path, which can be set with the environment variable XIC_LIB_PATH. The default path is

( . /usr/local/share/xictools/xic/startup ).

The default technology file has been provided by your system administrator. A personalized version can be generated with the Save Tech command.

The technology file generally begins with comment lines explaining the process that the file supports. The order of the sections that follow is rather flexible, though the printer driver blocks should appear last. It is recommended that one follow the ordering described here, which is the order used by Xic when generating a technology file, to be on the safe side. None of the sections is required to exist. Technology files for XicII and Xiv are simplified, omitting the sections that apply to unsupported features.

At the top of the file are macro definitions using the Set or Define keywords, and !set lines for setting global variables. The introductory part of the file further consists of optional path specifications. The layer blocks follow, which is where the core information about the particular technology resides. The electrical layers are defined first, followed by user-defined design rules, followed by the physical layer definitions.

The physical layers are followed by the device blocks, where physical characteristics for device extraction are given. These are followed by script function definitions. Finally, there is a section containing display attribute specifiers and other parameters, and the hard-copy driver parameter blocks.

Long lines can be continued in the technology file by using backslash continuation. For example, the following would be read as one line:

This a line to be continued, the backslash \
must be the last character in the line.

The technology file has a macro facility which can be used to simplify the constructs and to customize the file to a particular variation of the technology.

The technology file may contain the following keyword/value pair near the top of the file:

Technology name
The name can be any character token (no white space allowed) and gives a name to the technology. This is not directly used by Xic, but but the name is placed in the macro name space of the macro preprocessor used when reading various types of input files, including the device library. The name is displayed in the status line of the main window, and is part of the information available for output in scripts and elsewhere.

DeviceLibrary libname
The libname is the name of a device library file which provides device outlines for use in schematics. If not given, the name defaults to ``device.lib''. The libname should be a file name, without any directory path. A file by that name should be found in the library search path on program startup.

ModelLibrary libname
The libname is the name of a model library file which provides SPICE models for use in SPICE output. If not given, the name defaults to ``model.lib''. A file by that name should be found in the library search path on program startup.

ModelSubdir dirname
The dirname is the name of a subdirectory of the directories of the library search path, in which are found SPICE model files. All directories of this name found in the library path will be searched for SPICE models. If not given, the name defaults to ``models''.

ReadCds filename
This is part of the Cadence^TM compatibility package (see 2.7). The filename is the name of or path to a design resource or text-mode technology file. The full path should be given unless the file is in the library search path. This keyword should appear twice, first for the design resource file, and again for the (Cadence) technology file, if these are separate files. This will define the physical layers and attributes such as colors and fill patterns. Layers defined in the present Xic technology file will be in addition to these.