gEDA-user: SPICE & gaf

[Scott Dattalo]

Scott Dattalo wrote:
> Stuart's tutorials on using SPICE with gaf are well written and easy 
> to follow. Unfortunately, they need to be updated. Specifically, 
> loading the schematics in gEDA/examples/RF_Amp (which are packaged in 
> the 20061020 gaf release), give warnings like:
>
> Loading schematic 
> [/home/scott/projects/platypus/spice/ex_RF/MSA-2643.sch]
> WARNING: Symbol version mismatch on refdes C1 (capacitor-1.sym):
>       Symbol in library is newer than instantiated symbol
>       Minor version change (file 0.100, instantiated 0.000)
>
> Similar warnings also exist when the schematic is netlisted:
>
> $ gnetlist -g spice-sdb -o MSA-2643.cir MSA-2643.sch

This warning is cleared up by simply updating all components (e.g. 
select the components followed by typing 'ep').
> However the netlist encounters an error too (and is probably related 
> to the warning):
>
> Found a pin [X2] on component [2] which does not have a label!
> Using SPICE backend by SDB -- Version of 12.27.2005
> schematic-type = .SUBCKT Q1_MSA26F
> ERROR: In procedure <:
> ERROR: Wrong type argument in position 1: #f

This error is fixed in two steps. First, on the high level MSA-2643.sch, 
edit the transistor symbols and assign pinlabels to all of the pins. 
Then second, push down into X1 and X2 and assign the same names to the 
spice I/O connectors.

After this, all errors and warnings are removed from the gnetlist output.

At this point, the MSA-2643.cir produced by gnetlist exists, but cannot 
be simulated in ngspice. First of all, unlike the MSA-2643.cir packaged 
in 20061020 gaf, the one produced by gnetlist creates a SPICE .SUBCKT. I 
suspect some assumptions about hierarchical schematics are being violated.

Now, if I use the '-g spice' instead of the '-g spice-sdb' gnetlist 
guile backends, I get vastly different results. In particular, the spice 
backend output has numerous ' <No valid value attribute found>' errors 
in the .cir output.

That leaves me stuck again. Unless someone has more suggestions, I'll 
let this one sit for a while longer before picking it up again.

Scott