GDSII Stream format is the standard file format for transfering/archiving 2D graphical design data. It contains a hiearchy of structures, each structure containing. Beyond that, let me say that the stream format is quite simple. I suspect that the people at Calma put a lot of thought into creating a file that. Learn files and view a list of programs that open them.
|Country:||Papua New Guinea|
|Published (Last):||21 June 2017|
|PDF File Size:||19.89 Mb|
|ePub File Size:||3.93 Mb|
|Price:||Free* [*Free Regsitration Required]|
Starts with name of the first library and is followed by the second. An example MASK list looks like this: From Wikipedia, the free encyclopedia.
This means that all stream files should have an even number of bytes. This, along with the record length, flrmat the parser what to expect in the rest of the record.
As you can imagine, computers and processors have come a long way since that time; the specification has some constraints which were probably based both on the limitations of the 80’s era computers and also on the developer’s beliefs that chips were going to be approximately the same complexity for the foreseeable future.
I doubt anyone has had the chutzpah to start using it since. The leftmost bit of the first byte is valued atthe rightmost bit of the second byte is valued at 1.
GDSII – Wikipedia
It is an integer between and Values are 0, 3, 4, 5, and Binary The database is binary for compactness. Byte swapping is required when reading or writing integers with a little-endian machine, such as a VAX. Various companies including Artwork have developed their own gdsii binary-ascii converters for those who wish to use tools such as Perl, awk or Python to manipulate GDSII data.
If this record is omitted, then all bits are assumed to be 0. Records can be infinitely long. While other formats have been proposed to replace it and one, OASIS, seems to be gaining some traction GDSII remains by far the main way of describing the hdsii layout for the masks used to build a chip.
GDS II (Calma GDS II)
Typically, the first number is less than 1, since you use more than 1 database unit per user unit. The decimal point of the binary mantissa is just to the left of bit 8. Geometrical objects may also be tagged with “datatypes”, which can be used for any purpose, but are most commonly used to group together similarly sized objects for compensation of the proximity effect.
This marks the beginning of a structure reference element a reference or “call” to another cell in the library. Filw these attributes were designed to correspond to the “layers of material” used in manufacturing an integrated circuit, their meaning rapidly became more abstract to reflect the way that the physical layout is designed.
The reference library names may include directory specifiers separated with “: Order the complete book from SPIE.
Layers and datatypes used for mask in a filtered stream file. The more significant bytes appear first in the file, so that by default no byte swapping is required when reading the integers with a big-endian CPU e. Note that the data type e. Contains four bytes which specify in database units the extension of a path outline beyond the first point of the path. This page was last edited on 27 Novemberat The actual stream file: A polygon exceeding this limit will be split by default.
The elements within braces must occur one or more times. Same basic thing as a two byte integer, formta with four bytes. The record number is shown in brackets. The third data type is a “Two-Byte Signed Integer”. The following records are not fils by Stream Release 3.
The value of the text type must ge in the range of 0 to This record is present only if there is an attribute definition file bound to the library. Four-byte signed integer 3. The value can be negative. It is a binary file format representing planar geometric shapes, text labels, and other information about the layout in hierarchical form.
This is another artifact of the 16 bit words that the stream file format assumes.