GDS stream version

This is covered in the <ICinstDir>/doc/transref/transref.pdf (or <ICinstDir>/doc/transrefOA/transrefOA.pdf if using IC61X versions). There is a section about Stream Format, and within that a section called "Differences in Stream Format Versions". I've cut and pasted the relevant (slightly edited) section below. Note that in practice I've not seen anyone including the features introduced in versions 4/5/6. With version 7, it's primarily the limits being removed, and many people ignored the limits even in earlier stream versions. Given that even version 6 dated from Calma days (so more than 20 years ago, I think), it's usually not worth worrying about!

Differences in Stream Format Versions

There are five available versions of stream format, version 3, 4, 5, 6 and 7. Stream versions
4 and 5 are the same. The records listed in the above section are a combined list of all the
records supported by the various stream formats. The various versions provide support for a
subset of records present in this list.
The Stream format is usually broken down into 4 versions:

• Stream format version 3 supports basic geometric information. From the list of supported stream records, Stream 3.0 only supports up to record 44.
• Stream format version 4 or 5 provides support for geometric information along with supporting new types in gdsII 4, such as nodes, ports, template, plex data. From the list of supported stream records, version 5.2 supports up to record 56.
• Stream format 6, has some additional information for a product called "Custom Plus" that includes things like "attach file" and "lib access control lists". From the list of supported stream records, version 6.0 supports up to record 59.
• The last format version is generically called 7 which has lots of the limits removed. In this version, polygons can have more than 200 points, more than 64 layers and datatypes are supported, and more than 10 levels of hierarchy are supported. From the list of supported stream records, version7 supports all the records.

Stream 6 was very GDSII specific so not many non-Calma reader/writer applications handle
it. Simple applications deal with Stream 3 (basic geometries), more advanced deal with 4/5
and general purpose remove limitations and can handle upto version 7.

Regards,

Andrew

This is covered in the <ICinstDir>/doc/transref/transref.pdf (or <ICinstDir>/doc/transrefOA/transrefOA.pdf if using IC61X versions). There is a section about Stream Format, and within that a section called "Differences in Stream Format Versions". I've cut and pasted the relevant (slightly edited) section below. Note that in practice I've not seen anyone including the features introduced in versions 4/5/6. With version 7, it's primarily the limits being removed, and many people ignored the limits even in earlier stream versions. Given that even version 6 dated from Calma days (so more than 20 years ago, I think), it's usually not worth worrying about!

Differences in Stream Format Versions

There are five available versions of stream format, version 3, 4, 5, 6 and 7. Stream versions
4 and 5 are the same. The records listed in the above section are a combined list of all the
records supported by the various stream formats. The various versions provide support for a
subset of records present in this list.
The Stream format is usually broken down into 4 versions:

• Stream format version 3 supports basic geometric information. From the list of supported stream records, Stream 3.0 only supports up to record 44.
• Stream format version 4 or 5 provides support for geometric information along with supporting new types in gdsII 4, such as nodes, ports, template, plex data. From the list of supported stream records, version 5.2 supports up to record 56.
• Stream format 6, has some additional information for a product called "Custom Plus" that includes things like "attach file" and "lib access control lists". From the list of supported stream records, version 6.0 supports up to record 59.
• The last format version is generically called 7 which has lots of the limits removed. In this version, polygons can have more than 200 points, more than 64 layers and datatypes are supported, and more than 10 levels of hierarchy are supported. From the list of supported stream records, version7 supports all the records.

Stream 6 was very GDSII specific so not many non-Calma reader/writer applications handle
it. Simple applications deal with Stream 3 (basic geometries), more advanced deal with 4/5
and general purpose remove limitations and can handle upto version 7.

Regards,

Andrew