open-source-silicon.dev

Hey everyone, I'm trying to netlist a sky130 xschem schematic using the xschem CLI, but everytime it give me the following error.  Does anyone know how to fix this?

global_spice_netlist(): problems opening netlist file

Actually I figured out that it works if I don't specify the output location as a CLI option.

So I just deleted the "-o" option and it worked:
`xschem \`
    `--netlist --spice --no_x --quit \`
    `--rcfile xschemrc \`
    `-o /workspaces/bandgaps/.viper/netlists/test.spice \`
    `${SCH_FILE}`

Is this because there is a conflict with the following line in my xschemrc?

`set netlist_dir /workspaces/bandgaps/.viper/netlists`

<@U01UWL8PU87> the -o is used to specify the directory where the netlist goes. The filename is either taken from the circuit name (with .spice extension) or specified with -N:

`xschem --netlist --spice --no_X --quit --rcfile xschemrc -o /workspaces/bandgaps/.viper/netlists -N test.spice ${SCH_FILE}`

The reason for the two separate options for path and for filename is because there is a *split netlist mode* where xschem outputs each subcircuit netlist into a separate file (this is sometimes preferred when compiling / elaborating VHDL or Verilog or mixed digital designs). In this case only the destination path makes sense.

<@U01UWL8PU87> I will take a note to allow in the future full path specification of the netlist file  with -N (makes sense since in 99.9999% of the cases split netlisting mode is not used)

I agree, allowing the -N to include the full path is good.

The other thing I have to do after netlisting a design is post-process it to remove the comments around the top-level subckt and ends statement so I can use the Netlist as a spice lib and include it in another Netlist.

It would be helpful if there was a --lib option to do this.

<@U01UWL8PU87> If you add: `--tcl 'set lvs_netlist 1'` the top level .subckt will be uncommented. This is often used also for LVS. Also if you update your xschem now the -N accepts full path for netlist file.

Awesome, I'll give those a shot.  Thanks <@U01819B63HP>!