open-source-silicon.dev

Morning everyone, one quick question, I'm trying to set the grid at 0.005um, but it remains at 0.01um. I was searching here and <@U016EM8L91B> mentioned <https://open-source-silicon.slack.com/archives/C016HUV935L/p1607187865418900|here> to use `snap internal`  but it didn't change it. Does anyone have any idea?

Which technology file?  Both sky130 and GF180MCU should have a minimum grid setting of 5nm.
You should start magic with the `-rcfile` switch (e.g., `magic -d XR -rcfile /path/to/sky130A.magicrc`), which runs (among other things important to the PDK setup) a grid scaling that scales from lambda (an initial grid scaling chosen somewhat arbitrarily) to the minimum manufacturing grid.  If you're not using `-rcfile` (hint:  you should), you can scale the grid down with the `scalegrid` command.

I was working with sky130. Thanks Tim, I'll start using the rcfile.

<@U016EM8L91B> a little doubt. Once I open magic with the rc file and set `grid 0.005um 0.005um`, I still have to run `snap grid` because without it I can't work with the smallest dimensions.

Now, let's say I type the above commands and also paint some lines using `source` command (because they are described in a tcl file) and save all of that. Once I want to open it again, nothing is saved, I have to type one more time the `snap grid` and source the tcl file with the lines again.

Is there a solution to keep the effect of those commands in my previous work session?

First:  The `grid` command just draws grid lines.  If you want to draw on the fine scale, just use `snap internal` (what you did is fine, too, just a bit more roundabout).
If you are drawing geometry from the command line (or a script file), the `grid` and `snap` are irrelevant as long as you specify units (e.g., `box 10um 10um 20um 20um;  paint m1`)
"save all of that" followed by "nothing is saved" is contradictory.  Can you provide an example of something you scripted?  (A common misunderstanding is using the `save` command instead of the `writeall` command, which could be the issue here.)