Template Format

Schematics are drawn normally but statements can have special syntax that is substituted by CACE. The syntax follows three essential rules:

1. Condition and variable names in the project specification file are written in the schematic in braces prefixed with “CACE”, so “temperature” in the project file is “CACE{temperature}” in the schematic.

2. Expressions involving equations using condition and variable names are written in the schematic in brackets prefixed with “CACE”, so, for example, half of condition vdd would be written “CACE[CACE{vdd} / 2]”. These expressions are evaluated in python, so any arithmetic python expression that evaluates to a valid result may appear inside the brackets.

3. There are a handful of reserved variable names that are automatically substituted by CACE if they appear in the schematic:

• CACE{filename}

  The root name of the schematic file.

• CACE{simpath}

  The path to the simulation directory.

• CACE{root}

  The root path of the project.

• CACE{DUT_path}

  The full path to the DUT subcircuit definition netlist.

• CACE{DUT_name}

  The name of the DUT subcircuit

• CACE{netlist_source}

  The current netlist source such as: schematic, layout, pex or rcx.

• CACE{jobs}

  The number of jobs (threads) allocated for this simulation run. Should be used to set num_threads.

• CACE{PDK_ROOT}

  The path to the directory containing the PDK

• CACE{PDK}

  The name of the PDK

• CACE{N}

  This is substituted with the simulation index. Most often used as a filename suffix for the output data file.

• CACE{random}

  A random integer number.

• CACE{cond=value}

    For any condition cond, this form indicates that "value" is
    to be subsituted for the condition if the condition is not
    declared in the CACE project file.
  

• CACE{cond|minimum} {cond|maximum} {cond|stepsize} {cond|steps}

  Instead of substituting one value for a condition, a value over all conditions is substituted, including the maximum over all conditions, minimum over all conditions, the step size between neighboring condition values, or the number of steps over all values of the condition. This is used most often in cases where a condition is handled entirely inside a testbench netlist (such as in a sweep), and not iterated over multiple netlists.