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ferg_jl
October 11th, 2002, 11:58
Hi,

I have recently been studying modelsim 5.6d and have exctracted what I belive are the correct seeds. So I generated a license and everythign seems to be fine, except the simulator crashes when I try to certain operations. This puzzled me, is this something to do with the license or the setup of the simulator??

So I got a known good license and crypted it using my seeds. The keys on the feature lines are not the same!!!..

My question is two license files with the same seeds are generated at very different times have the same keys??..

If they will have the same this means that I have the wrong seeds or modesim is doing an extra level of encryption, I have already traced all the calls to lc_set_attr and it does not use crypt filters and nothing else that looks like it is using anything extra.

Am I missing something? ..Has anyone had any experence will modelsim?...Is there something else I need to look for

BTW modelsim is using 6.1g

Cheers

J

Avalonder
October 12th, 2002, 18:33
Hi ferg_jl,

i've had problems too, when i moved from 5.6b to 5.6d. The feature line keys are generated with verfmt 5.1, so they have encrypted the start date at four positions in the key. If this start date is not equal to that of your known good license, the keys will differ. If you omit the start date in the license (source) file, lmcrypt will use the current date. MSIM 5.6d checks the start date range, also license duration (permanent isn't possible any more with floating licenses) and the host id can't be of type ANY. For example a license source line should look like this:

FEATURE featurename vendordaemon 2002.08 end-date 10 start:01-oct-2002

After crypting this line, the start date is encrypted in the key. You should study the range checks, and find out the correct bounds for start date, end date and also version number. Look in routines (vlm.exe) where lc_auth_data is called. When you take care of this checks in your license file, most problems should be solved.

BTW there is still another problem with 5.6d and the LEON project. The simulator crashes in iu.vhd. This problem can be fixed, when compiling the project with vcom from 5.6b. This can be a bug in vcom, because it dosn't use flexlm anymore, but may be also, that vcom checks for certain entries in some *.ini files, and when missed them, vcom restricted the memory usage to the evaluation version.

ferg_jl
October 13th, 2002, 20:25
Thx, thats done it.

J