Add support for Ngspice mixed analog/digital simulation

[ra3xdh]

Ngspice team has recently added two XSPICE devices: d_process and d_cosim. These devices allows to simulate the component defined as Verilog/VHDL code with analog schematic. It's need to add support for such device from Qucs-S GUI.

[2nOrderEDO]

This would be wonderful to have.

[tomhajjar]

What syntax/version/flavor of Verilog is going to work? Many of the old Qucs 0.0.19 Verilog projects didn't work under Qucs-S.

[2nOrderEDO]

What syntax/version/flavor of Verilog is going to work? Many of the old Qucs 0.0.19 Verilog projects didn't work under Qucs-S.

I think that would depend on ngspice.