Cadence Custom IC Design Forum

help with Abstract generator

sardar1 — Wed, 19 Jun 2013 10:39:54 GMT

Dear friends

First of all I take this oppertunity to say hi , I hope to have a great, honorable and informative virtual kinship with all of you.

The problem I am facing is with the Abstract generator, I have a few verilog modules that are nested and I have created their GDS through encounter. I imported that GDS in abstract generator and want to create a one cell lef. Now that I run the pin step the tool constantly gives me error ABS- 520 "cannot create net named "xyz" from the database".

If I give a single module it creates its lef but If I give the same module as an instiation it gives me this error. Any form of help will be highly appreciated.

Thanks in advance

sardar

spectremdl and "print fmt" function

samung — Wed, 19 Jun 2013 09:29:17 GMT

Hello !!

I would like to use the "print fmt" function of spectremdl, however, I have not managed yet in printing something in an ouput file with this function.

I have written some extracted data from a transient simu with export command but the "print fmt" doesn't work for me.

I would like to better configure what is inside the results_file, meaning removing the default template :

"Exported variables from results directory: ./input.raw

date : 31:18:59 AM, Wed Jun 19, 2023

design : (no title)

simulator : spectre"

I launch : spectremdl -batch input.mdl -design input.scs -measure results_file +log log_file.log

I have the following input.mdl file :

/* mdl measurement file */

alias measurement run_tran_simu {

input string out="aaa/bbb/ccc/results_file"

run tran

export real out_value_50n = V(out)@50n

export real out_value_0 = V(out)@0

export real diff_out_50n_0 = abs(V(out)@50n - V(out)@0)

print fmt ("****Cell functionnality : TEST****") addto=out

if (diff_out_50n_0 > 1)

{

print fmt ("****Cell functionnality : GOOD****") addto=out

}

else

{

print fmt ("****Cell functionnality : BAD****") addto=out

}

run run_tran_simu

and the following results_file :

Exported variables from results directory: ./input.raw

date : 31:18:59 AM, Wed Jun 19, 2033

design : (no title)

simulator : spectre

Measurement Name : run_tran_simu

Analysis Type : tran

diff_out_50n_0 = 1.1

out_value_0 = 1.1

out_value_50n = 4.89856e-06

NB : we don't see any "print fmt" written stuff !!

The log file is clean :

sam@clust:/xxx/yyy/.../zzz> grep -i error log_file.log

spectre completes with 0 errors, 0 warnings, and 3594 notices.

How can I do to use this "print fmt" function with success ? How can i customize the "template" of the results_file ??

Thanks !!

Changing layer numbers in a design library

Lynks — Tue, 14 May 2013 21:03:27 GMT

We created a library using a custom technology file where different layers were assigned arbitrary layer numbers in IC6.1.5-64b.500.8. Now we want to take that same library and use it with a much larger technology file which will add additional layers and include all layers previously defined in the custom technology file we had. Unfortunately, there are some conflicts in the layer numbers.

At this point, we've edited the larger technology file so that all the layers from the custom technology file have been assigned to available layer numbers. Now because the layer numbers are different, the polygons in the design library do not show (only the polygons whose layers just so happened to have the same layer number as it originally had actually showed correctly).

One idea we've tried is to stream out the design library to a GDS file and create a layer mapping. I would take take the layer name that was obtained from the custom tech file and map it to a stream layer number. The stream layer number I'd choose would be the same number as this layer would appear in the larger tech file. Then I would stream-in the GDS file back into Virtuoso with the larger tech file attached. Even in this manner, I got a similar result as mentioned previously. As a test, I streamed in the GDS file again with the custom tech file attached instead and everything looked good. It seems like the layer mapping didn't affect the layer numbers. Perhaps, I missed an important step here.

In the end, I simply want this design library which was originally made using a custom tech library, to work with this larger manually merged tech file where the same layers from the custom tech library are now using different layer numbers. Does anyone know of a simple way to do this?

Any help is appreciated.

Exporting images for CDF forms to generate cellview documentation

Herge — Tue, 18 Jun 2013 19:37:25 GMT

For cellviews there exists a function "hiExportImage" which allows to generate an image file for a given cellview, opened in a (eventually hidden) window -- at least this is what I've understood. This should allow me to generate illustrations for all cells in a library automatically. Nice.

My question is about CDF forms : How could I automatically export images for CDF forms ? There is a "hiWindowSaveImage" function which can take handles to different types of objects including windows and forms. So the problem would boil down to getting the handle to the CDF form of interest. And here I am stuck -- I don't see how to programmatically get a handle to the CDF form associated to a particular cell.

Any suggestions ?

"Instance name is not unique" even though there are no instances named like so

kitmonisit — Fri, 24 May 2013 08:48:23 GMT

I am trying to rename an instance to, for example, K0, but I get an error (SCH-1025): Instance name "K0" is not unique. I am sure that there are no other instances currently named K0 in the schematic.

Is this a bug?

I think this is a cache problem. Is there a way I can clear the cache of instance names?

Dynamic abstract generation in layout XL

Sandeep4386 — Tue, 18 Jun 2013 20:36:22 GMT

I was going through abstract generator user guide, I din't quite understand what's the main benifits of using dynamic abstract generation? I get it that it can create abstracts for the pcell on the fly, but can't we achieve same thing using regular abstract generator?

Could anyone brief me about motivation behind using daynamic abstract generator?

Regards,

Sandeep

How to probe parasitics in QCR

rffrog — Tue, 18 Jun 2013 20:33:37 GMT

Dear all,

I have some difficulties in probing parasitcs in cadence QCR. My cadence version is 06.15 with pve package installed.

I browsed some technical guide, in which parasitic probing is done through Tools-->Parasitics to recall MSPS, but I cannot find this option in my menu bar.

What I found is by chosing Verify--> LVS in the extracted view, I saw Parasitic Probe, I chose Whole Net and clicked on a net in the extracted view, but no window popped up. Supposedly, a window shall pop up summarizing all the parasitics, is it right?

Any help will be appreciated!

dx/dy question in IC6

SUEE — Mon, 17 Jun 2013 18:13:40 GMT

In IC5 virtuoso layout editor, when we do "copy" or "move" a object, the dx/dy column in menu bar will show the relative distance we move the object. But in IC6, it does not show any number there.

What should I do to active the dx/dy result?

Many thanks !!

Fatal Application Error in ASSURA av_extracted

Bayes — Tue, 18 Jun 2013 08:55:51 GMT

Hi,

I am using 6.1.5 environment and I'm running ASSURA to perform DRC and LVS and it is all right.

Unfortunatelly, then, when I try to run Assura Parasitic Extraction, to generate an extracted view (av_extracted), I have a serious problem since I have the crash of CADENCE and I don't understand where is the problem.

In attachment there are the window that appears when there is the system crash and the related generated log files.
What's happening? What can I do to solve this error/problem?

Thanks a lot in advance for your help,

Andrea.

spectremdl issue : syntax error before or at: trans invalid argument to run statement

samung — Tue, 18 Jun 2013 09:07:22 GMT

Hello !

I am a new user of spectremdl and I make a basic trial, just to check that it works. I want to print a value in a result file.

I don't know why, I have the below log file issues, and especially : syntax error before or at: trans invalid argument to run statement

I launch (through a job queue) : spectremdl -batch input.mdl -design input.scs -measure results_file

log file :

Simulating `input.scs' on clust at 30:52:56 AM, Tue Jun 68, 2033 (process

id: 115827).

Error found by spectre.

ERROR: line 11, column 5: syntax error before or at: trans

invalid argument to run statement

ERROR: line 11, column 10: syntax error before or at: <eof>

unrecognised statement

ERROR (MDL-6): Failed to parse MDL control file, `input.mdl'.

input.mdl :

alias measurement trans {

input real test_var = 13

run tran_simu

export test_var

}

run trans

input.scs extract :

simulator lang=spectre

global 0

include "xxx/corners_FF.scs"

parameters nmos_tran_model=nsvtlp pmos_tran_model=psvtlp wpen=xxx wneqi=xxx ... Rright=10 ... lneqi=xxx lndiff=xxx ...

subckt inv A1 YN vdd vnw vpw vss

parameters wp=xxx lp=xxx pfolds=1 wn=xxx ln=xxx nfolds=1

M5 (YN A1 vdd vnw) psvtlp w=wp*10e5 l=lp*10e5 nfing=pfolds mult=1 srcefirst=1 mismatch=1 lpe=0 numcos=1 numcod=1 ngcon=1

M2 (YN A1 vss vpw) nsvtlp w=wn*10e5 l=ln*10e5 nfing=nfolds mult=1 srcefirst=1 mismatch=1 lpe=0 numcos=1 numcod=1 ngcon=1

ends inv

// View name: schematic

subckt ncx ncx

ends ncx

// End of subcircuit definition.

Rleft (vli saout_b) resistor r=Rleft

...

M2 (saout saeqi saout_b vpw) nsvtlp w=xxx l=xxx nfing=1 mult=1 srcefirst=1 mismatch=1 lpe=0 numcos=1 numcod=1 ngcon=1

M1 (saout_b saout vss vpw) nsvtlp w=xxx l=xxx nfing=1 mult=1 srcefirst=1 mismatch=1 lpe=0 numcos=1 numcod=1 ngcon=1

M0 (saout net07 vss vpw) nsvtlp w=xxx l=xxx nfing=1 mult=1 srcefirst=1 mismatch=1 lpe=0 numcos=1 numcod=1 ngcon=1

M4 (vli signal1 vdd vnw) psvtlp w=xxx l=xxx nfing=1 mult=1 srcefirst=1 mismatch=1 lpe=0 numcos=1 numcod=1 ngcon=1

...

include ".../_graphical_stimuli.scs"

ic saout=xxx saout_b=0

simulatorOptions options reltol=1e-3 vabstol=1e-6 iabstol=1e-12 temp=70 tnom=27 scalem=1.0 scale=1.0 gmin=1e-12 rforce=1 maxnotes=5 maxwarns=5 digits=5 cols=80 pivrel=1e-3 sensfile="../psf/sens.output" checklimitdest=psf

tran_simu tran stop=10u write="spectre.ic" writefinal="spectre.fc" annotate=status maxiters=5

finalTimeOP info what=oppoint where=rawfile

modelParameter info what=models where=rawfile

element info what=inst where=rawfile

outputParameter info what=output where=rawfile

designParamVals info what=parameters where=rawfile

primitives info what=primitives where=rawfile

subckts info what=subckts where=rawfile

save signal1

saveOptions options save=allpub subcktprobelvl=2

Thanks a lot for your help !!