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I ran into a problem when testing a simple inverte...
# xschem
h
I ran into a problem when testing a simple inverter circuit. The signals that pops out when clicking the Waves button are just nonsense. However, the signals can be drawn using ngspice plot command. Did I do anything wrong with the gaw waveform viewer?
w
huh, that looks all correct
Are you sure you have the latest versions of everything?
i.e. the xschem version of gaw and ngspice / xschem built from source and not installed from the package manager?
try typing
Copy code
which ngspice
and
Copy code
which xschem
in the command line and see what the point to
they should all be installed in /usr/local/bin/
h
Yes, I checked their locations, ngspice is under /usr/bin/ngspice, xschem is under /usr/local/bin/, gaw is under /usr/local/bin.
actually, xschem and ngspice were installed using the package manager, but I had to download gaw from http://download.tuxfamily.org/gaw/download/ and unzip it.
And those random values popping out when invoking the gaw are actually not nonsense, but a bunch of physical constants, like c for the speed of light.
Only those physical constants are showing up even if I directly open the raw file with the gaw.
s
integration of xschem and gaw is working in recent versions, i suggest you to build xschem and gaw from here and here...
h
@Stefan Schippers I looked at the log and I found this... Do you know how to solve this? And yes the problem is still there after I build xschem and gaw from the repos.
s
Please explain better your problem. Do nets clicked in xschem (Alt-g) not show in gaw? the picture you sent shows correct inverter input and output. Do you have a crashing gaw? the message above could be just a failed gtk assertion, I have such messages on most gtk applications, so i don't care much about them. This is a gaw issue, not xschem. If the assertion causes program termination you should change some compiler option.
try to run 'gaw inverter .raw', you should see your transient waveforms. if not you don't have variables saved in the raw file.
h
Sorry, let me restate my problem. The problem is that gaw is not showing the right variables. In my schematic, I am expecting to see 'vin', 'vout' and other variables shown in the gaw. But I only see a list of variables like 'false', 'ture', 'boltz', 'planck' and etc, which are obviously not anything defined in the schematic. I also try to type the command 'gaw inverter.raw' in the terminal, but it has the same problem as stated above. I check under ~/.xschem/simulations and try to directly open the raw file, and I notice that the variables are wrong. I hope I make myself clear this time.
s
This is the set of constants that is saved if no other thing is saved. You should have another ascii header section (and binary blob following) with transient simulation results. Try this: 
.control
save all
tran 0.1n 100n
write inverter.raw
.endc
instead of mixing control block statements and .tran / .save. Run ngspice in interactive mode (no -b option)
h
It works. Thank you very much!
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