Cyclicity Simulation Engine Internal Modules - se_test_harness

The inputs and outputs are specified at instantiation time by string options to the module: the option string 'inputs' gives a string list of the inputs for the module; the option string 'outputs' gives a string list of the outputs for the module.

The module is always clocked, and has a single clock. The name of this is specified with a string option 'clock' at instantiation time.

The functionality of the module comes from an 'exec_file' whose name is passed in to the instantiation with the string option 'filename'. This exec_file supports the standard functions, plus those described in the section below.

All the options (the above named ones and any others given to the instance) are available inside the exec_file, so additional arguments may be passed to the functionality section of the module by using these options. For example, many of the regression tests pass a string to their test harness that contains the name of the particular test to run, and that test data is gathered from a memory which can be preloaded with a MIF file derived from that test name.

The exec_file enhancements it itself supplies basically are a small set of commands to control its inputs and outputs, and to do time control.

reset( string output signal name, integer value )

Immediately set an output to a value; does not wait for the next clock edge. This should be used for reset signals, for example. Most everything else should be clocked (i.e use the drive command).

drive( string output signal name, integer value )

On the next clock edge set the output signal name to the given value

wait( integer number of cycles )

Wait the given number of cycles

wait_until_value( string input name, integer value )

Wait until the input signal hits the given value; this signal is tested just prior to every clock edge.

wait_until_change( string input name )

Wait until the input signal changes; this signal is tested just prior to every clock edge.

integer input( string input name )

Get the current integer value of an input