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<@U01819B63HP> I have troubles with `device_param_probe.sym`, I struggle to get it working. Any hints?

I just realized that the `nfet/pfet_*_nf` are missing the `id` and `gm` expressions, could you please add them there as well? And they sometime work and sometime now, do you have an idea what could go wring? Is the `save all` sufficient?

I did a bit of debugging, and here a few things:

• Before the `write XYZ.raw` a `remzerovec` is helpful to fix issues with non-zero vectors.
• The `gm` values need an extra `save @m...[gm]` statement.
<@U01819B63HP> Any chance that you could put these `save [gm]` statements automatically into the simulation controls? For many transistors, this is quite difficult. Or is there a way like the `save all`  but for device parameters?

<@U02UAUGSQ22> the options I use to save most variables are `.options savecurrents` and `save all`:
```.options savecurrents
...
...
.control
  ...
  save all
  tran 1n 200n
  remzerovec
  write dile.raw
.endc```
these two save options will dump all currents (including device internal currents) to the raw file.
for
 other parameters, like gm, vth and others, these must be specifically
saved with a save instruction for every transistor, and as far as i know
 wildards are not accepted:
```save @m.x1.xm5.msky130_fd_pr__nfet_01v8[gm]
save @m.x1.xm5.msky130_fd_pr__nfet_01v8[gds]
save @m.x1.xm5.msky130_fd_pr__nfet_01v8[gmbs]
save @m.x1.xm5.msky130_fd_pr__nfet_01v8[vth]```
The
 syntax for saving device parameters is really ngspice specific. Xyce
will use a totally different (and cleaneer) syntax,  I am not even sure
if every internal parameter is available.
For the `remzerovec`
 i also struggled a lot with this. It happens I believe when body
currents are zero (low injection) and then no vector is saved. I hope
the ngspice devs will fix this autmatically in the future...
Will add the gm/id printouts in the _nf fets.
For the view_only_probes dimming the circuit is a good idea, will work on that, will take a bit of time. Thanks (edited)

<@U02UAUGSQ22> using `.options savecurrents` and looking into the header of the raw file you find the syntax of all fet currents:
`i(@m.x2.xm2.msky130_fd_pr__nfet_01v8_lvt[id])`
Getting other parameters, for example `gm` is easy:
`@m.x2.xm2.msky130_fd_pr__nfet_01v8_lvt[gm]`
so remove the `i(`...`)`, change `[id]` with `[gm]`, and give the resulting expression to a `save` statement.
For parameters that are voltages (like vth) replace i(...) with v(...)

<@U01819B63HP> That’s a good tip, thank!

1.png

<@U02UAUGSQ22> I have done the change, if only probes are enabled the schematic is dimmed instead of hidden:

<@U01819B63HP> that looks amazing, thanks!