Xschem example circuits should not contain `pre_osdi`

[hpretl]

In situations where the VerilogA models are located in a central location (not in various simulation directories, but e.g. in .../ngspice/lib/ngspice) the pre_osdi directive leads to an error when starting ngspice.

As a consequence, this directive should not be part of the "standard" examples. Alternatively, it should be wrapped into a check whether this file exists in this local directory.

[olisnr]

i think the pre_osdi ./psp103_nqs.osdi belongs to the

https://gitlab.com/dmt-development/ihp_sg13g2_compact_models

[hpretl]

Yes, the statement pre_osdi loads the external PSP model into ngspice which is needed for the IHP MOSFET. But this model can be loaded from a central location with a central ngspice setting. Thus, the pre_osdi is not needed in every schematic.

[olisnr]

You would prefer ./simulation/.spiceinit then?

[hpretl]

Not really. In our Docker image we just copy psp103.osdi into .../ngspice/lib/ngspice, and uncomment the corresponding line in .../ngspice/share/ngspice/scripts/spinit:

* Load the OpenVAF/OSDI models
if $?osdi_enabled

 * osdi /foss/tools/ngspice/ngspice/lib/ngspice/asmhemt.osdi
 * osdi /foss/tools/ngspice/ngspice/lib/ngspice/bjt504t.osdi
 * osdi /foss/tools/ngspice/ngspice/lib/ngspice/BSIMBULK107.osdi
 * osdi /foss/tools/ngspice/ngspice/lib/ngspice/BSIMCMG.osdi
 * osdi /foss/tools/ngspice/ngspice/lib/ngspice/HICUMl0-2.0.osdi
 osdi /foss/tools/ngspice/ngspice/lib/ngspice/psp103.osdi
 * osdi /foss/tools/ngspice/ngspice/lib/ngspice/r2_cmc.osdi
 * osdi /foss/tools/ngspice/ngspice/lib/ngspice/vbic_4T_et_cf.osdi

end

This spinit is the default init ngspice reads.

[hpretl]

Since quite a few .osdi files are already there, and are included in the same way, it feels natural to add the PSP model there as well.