streamin pcell

[ruby]

Hi,
I streamed-out a gds file with an option to keep Pcells. When I
streamed-in back this gds file to a different library and I wanted to
keep the Pcells it won't let me do that.
Do you know what is the problem?
Also when I stream-in without the option to keep the Pcells I got many
cells with $$sign.
Thanks,
Ruby

 

[layoutDesign]

On Jan 9, 12:01 pm, ruby <ryehos...@gmail.com> wrote:

Hi,
I streamed-out a gds file with an option to keep Pcells. When I
streamed-in back this gds file to a different library and I wanted to
keep the Pcells it won't let me do that.
Do you know what is the problem?
Also when I stream-in without the option to keep the Pcells I got many
cells with $$sign.
Thanks,
Ruby

I use Cadence Parameterized cells. Once you streamout, and then
streamin, I don't think you will be able to have the parameterized
cells anymore. I think there are limitations to streaming out/in with
gds.

 

[Andrew Beckett]

layoutDesign wrote, on 01/09/09 21:10:

On Jan 9, 12:01 pm, ruby <ryehos...@gmail.com> wrote:
Hi,
I streamed-out a gds file with an option to keep Pcells. When I
streamed-in back this gds file to a different library and I wanted to
keep the Pcells it won't let me do that.
Do you know what is the problem?
Also when I stream-in without the option to keep the Pcells I got many
cells with $$sign.
Thanks,
Ruby

I use Cadence Parameterized cells. Once you streamout, and then
streamin, I don't think you will be able to have the parameterized
cells anymore. I think there are limitations to streaming out/in with
gds.

There is an option to keep pcells - it creates a side file with information
about the pcells, so that (in theory) can reverse the process upon stream in.

Personally I can never see the point of that - why not just use the original
database?

The problem is that if you change anything at all in the stream file (i.e. you
went through some external tool, or as seen here - you want to stream back into
another library), you've reduced the chance significantly of being able to
convert the fixed cells in the stream file back to pcell instances.

Sometimes people say they want to do this for archive purposes - well, just
archive the original Cadence library alongside the stream (GDS) that you taped
out - that's the best solution.

To Ruby - why are you trying to do this round trip?

Regards,

Andrew.

--
Andrew Beckett
Senior Solution Architect - Cadence Design Systems Ltd (UK)