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update docs (schematic generators)

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stefan schippers 2023-04-27 23:51:42 +02:00
parent 410135cf44
commit 3604f31e73
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124
doc/xschem_man/tutorial_symbol_generators.html
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@ -29,7 +29,8 @@ p{padding: 15px 30px 10px;}
The symbolgen generator in this example takes either a <kbd>(buf)</kbd> or a <kbd>(inv)</kbd> parameter
to generate a buffer or an inverter, respectively. If no parameters are given (empty parentheses) a buffer
is generated.<br>
In this example a tcl script is used, you can use any language you like.
In this example a tcl script is used, you can use any language you like. The script only needs to parse
the parameters (if any) and output on standard output a regular xschem symbol file.
</p>
<pre class="code">
#!/bin/sh
@ -40,49 +41,47 @@ set arg1 [lindex $argv 0]
if { $arg1 eq {inv}} {
puts {v {xschem version=3.1.0 file_version=1.2}
K {type=subcircuit
verilog_primitive=true
vhdl_primitive=true
vhdl_format="@@Y &lt;= not @@A after 90 ps;"
verilog_format="assign #90 @@Y = ~@@A ;"
format="@name @pinlist @symname ROUT=@ROUT"
template="name=x1 ROUT=1000"
schematic=inv_ngspice.sch}
xvhdl_primitive=true
xverilog_primitive=true
xvhdl_format="@@y &lt; not @@a after 90 ps;"
xverilog_format="assign #90 @@y = ~@@a ;"
format="@name @pinlist @symname wn=@wn lln=@lln wp=@wp lp=@lp"
template="name=x1 wn=1u lln=2u wp=4u lp=2u"
schematic=schematicgen(inv)}
L 4 -40 0 -20 0 {}
L 4 -20 -20 20 0 {}
L 4 -20 -20 -20 20 {}
L 4 -20 20 20 0 {}
L 4 30 -0 40 -0 {}
B 5 37.5 -2.5 42.5 2.5 {name=Y dir=out }
B 5 -42.5 -2.5 -37.5 2.5 {name=A dir=in }
B 5 37.5 -2.5 42.5 2.5 {name=y dir=out }
B 5 -42.5 -2.5 -37.5 2.5 {name=a dir=in }
A 4 25 -0 5 180 360 {}
T {@symname} -47.5 24 0 0 0.3 0.3 {}
T {@name} 25 -22 0 0 0.2 0.2 {}
T {Y} 7.5 -6.5 0 1 0.2 0.2 {}
T {A} -17.5 -6.5 0 0 0.2 0.2 {}
T {ROUT=@ROUT} -25 -42 0 0 0.2 0.2 {}
T {y} 7.5 -6.5 0 1 0.2 0.2 {}
T {a} -17.5 -6.5 0 0 0.2 0.2 {}
}
} else {
puts {v {xschem version=3.1.0 file_version=1.2}
K {type=subcircuit
verilog_primitive=true
vhdl_primitive=true
vhdl_format="@@Y &lt;= @@A after 90 ps;"
verilog_format="assign #90 @@Y = @@A ;"
format="@name @pinlist @symname ROUT=@ROUT"
template="name=x1 ROUT=1000"
schematic=buf_ngspice.sch}
xvhdl_primitive=true
xverilog_primitive=true
xvhdl_format="@@y &lt; @@a after 90 ps;"
xverilog_format="assign #90 @@y = @@a ;"
format="@name @pinlist @symname wn=@wn lln=@lln wp=@wp lp=@lp"
template="name=x1 wn=1u lln=2u wp=4u lp=2u"
schematic=schematicgen(buf)}
L 4 20 0 40 0 {}
L 4 -40 0 -20 0 {}
L 4 -20 -20 20 0 {}
L 4 -20 -20 -20 20 {}
L 4 -20 20 20 0 {}
B 5 37.5 -2.5 42.5 2.5 {name=Y dir=out }
B 5 -42.5 -2.5 -37.5 2.5 {name=A dir=in }
T {@symname} -47.5 34 0 0 0.3 0.3 {}
B 5 37.5 -2.5 42.5 2.5 {name=y dir=out }
B 5 -42.5 -2.5 -37.5 2.5 {name=a dir=in }
T {@symname} -47.5 24 0 0 0.3 0.3 {}
T {@name} 25 -22 0 0 0.2 0.2 {}
T {Y} 7.5 -6.5 0 1 0.2 0.2 {}
T {A} -17.5 -6.5 0 0 0.2 0.2 {}
T {ROUT=@ROUT} -25 -42 0 0 0.2 0.2 {}
T {y} 7.5 -6.5 0 1 0.2 0.2 {}
T {a} -17.5 -6.5 0 0 0.2 0.2 {}
}
}
</pre>
@ -90,69 +89,57 @@ T {ROUT=@ROUT} -25 -42 0 0 0.2 0.2 {}
The <kbd>generators/test_symbolgen.sch</kbd> is a test schematic that places two instancs of this
symbol generator, one as <kbd>symbolgen(buf)</kbd> and one as <kbd>symbolgen(inv)</kbd>.
The schematic implementations of these symbols are defined by the generator using a <kbd>schematic</kbd>
attribute. The buffer will use <kbd>buf_ngspice.sch</kbd> and the inverter will
use <kbd>inv_ngspice.sch</kbd>, these reused example schematics are present in
the <kbd>ngspice/</kbd> directory.
attribute. The buffer will use <kbd>schematicgen(buf)</kbd> and the inverter will
use <kbd>schematicgen(inv)</kbd>, these schematic names are referencing a schematic generator
script instead of regular schematic files. See next section about schematic generators.
</p>
<img src="symbol_generators02.png">
<p>
The following is the extracted netlist from this example:
</p>
<pre class="code">
** sch_path: /home/schippes/xschem-repo/trunk/xschem_library/generators/test_symbolgen.sch
**.subckt test_symbolgen
x1 IN_INV IN symbolgen_inv ROUT=1200
x3 IN_BUF IN symbolgen_buf ROUT=1200
x1 IN_INV IN symbolgen_inv wn=1u lln=2u wp=4u lp=2u
x3 IN_BUF IN symbolgen_buf wn=1u lln=2u wp=4u lp=2u
C1 IN_BUF 0 100f m=1
C2 IN_INV 0 100f m=1
**** begin user architecture code
.param vcc=1.8
Vin in 0 pwl 0 0 10n 0 10.1n 1.8 20n 1.8 20.1n 0
.include models_rom8k.txt
.param vcc=3
vvcc vcc 0 dc 3
Vin in 0 pwl 0 0 100n 0 100.1n 3 200n 3 200.1n 0
.control
save all
tran 0.2n 30n uic
tran 1n 300n uic
write test_symbolgen.raw
.endc
**** end user architecture code
**.ends
* expanding symbol: symbolgen(inv) # of pins=2
** sym_path: /home/schippes/xschem-repo/trunk/xschem_library/generators/symbolgen
** sch_path: /home/schippes/xschem-repo/trunk/xschem_library/ngspice/inv_ngspice.sch
.subckt symbolgen_inv Y A ROUT=1000
*.ipin A
*.opin Y
B1 net1 0 V = 'VCC/2*(1-tanh((V(A1)-VCC/2)*100))'
R1 Y1 net1 'ROUT' m=1
C1 A1 0 8f m=1
C2 Y1 0 8f m=1
V1 Y Y1 0
.save i(v1)
V2 A1 A 0
.save i(v2)
** sch_path: /home/schippes/xschem-repo/trunk/xschem_library/generators/schematicgen
.subckt symbolgen_inv y a wn=1u lln=2u wp=4u lp=2u
*.opin y
*.ipin a
m2 y a VCC VCC cmosp w=wp l=lp ad='wp *4.6u' as='wp *4.6u' pd='wp *2+9.2u' ps='wp *2+9.2u' m=1
m1 y a 0 0 cmosn w=wn l=lln ad='wn *4.3u' as='wn *4.3u' pd='wn *2+8.6u' ps='wn *2+8.6u' m=1
.ends
* expanding symbol: symbolgen(buf) # of pins=2
** sym_path: /home/schippes/xschem-repo/trunk/xschem_library/generators/symbolgen
** sch_path: /home/schippes/xschem-repo/trunk/xschem_library/ngspice/buf_ngspice.sch
.subckt symbolgen_buf Y A ROUT=1000
*.ipin A
*.opin Y
B1 net1 0 V = 'VCC/2*(1+tanh((V(A1)-VCC/2)*100))'
R1 Y1 net1 'ROUT' m=1
C3 Y1 0 8f m=1
C1 A1 0 4f m=1
V1 Y Y1 0
.save i(v1)
V2 A1 A 0
.save i(v2)
** sch_path: /home/schippes/xschem-repo/trunk/xschem_library/generators/schematicgen
.subckt symbolgen_buf y a wn=1u lln=2u wp=4u lp=2u
*.opin y
*.ipin a
m2 net1 a VCC VCC cmosp w=wp l=lp ad='wp *4.6u' as='wp *4.6u' pd='wp *2+9.2u' ps='wp *2+9.2u' m=1
m1 net1 a 0 0 cmosn w=wn l=lln ad='wn *4.3u' as='wn *4.3u' pd='wn *2+8.6u' ps='wn *2+8.6u' m=1
m3 y net1 VCC VCC cmosp w=wp l=lp ad='wp *4.6u' as='wp *4.6u' pd='wp *2+9.2u' ps='wp *2+9.2u' m=1
m4 y net1 0 0 cmosn w=wn l=lln ad='wn *4.3u' as='wn *4.3u' pd='wn *2+8.6u' ps='wn *2+8.6u' m=1
.ends
.GLOBAL VCC
.end
</pre>
<p>
@ -161,6 +148,15 @@ V2 A1 A 0
<kbd>symbolgen inv hv 100</kbd> and take the standard output from the script as the symbol
file to load and display.
</p>
<h2> Schematic generators </h2>
<p>
The same approach used for symbol generators can be used for schematic generators. If you add a
<kbd>schematic=schematicgen(buf,4)</kbd> attribute to an instance
xschem will look for a script named <kbd>schematicgen</kbd> in the search paths and call
it with the given parameters (that is, execute the command
<kbd>schematicgen buf 4</kbd>) and read the produced output as a schematic file.
</p>
<img src="symbol_generators03.png">
<br><br><br>
<!-- end of slide -->
<div class="filler"></div>