How not to capture Simulation Data during a specified simulation duration

Description

Is there a way to run the simulation so that the simulation data doesn't get captured until some user specified time into the simulation?

Solution 1

In your script file, you can make changes similar to the following example:

Example:
asim +access+r top
log UUT/*
run 100 ns
asdbdump -off
run 10 us
asdbdump -on
run 200 ns

In above example, simulation is initialized with asim command and all signals are logged from UUT/* region with log command. Logging continues for 100ns(run command) and then it is disabled for 10us (with asdbdump -off command). It is then re-enabled(with asdbdump -on command) for another 200ns.

Note that signals with disabled logging remain visible on Accelerated Waveform Viewer. The value displayed on the waveform is equal to last value recorded at the time point when logging was disabled.

Solution 2

In your script, try something like below example:

Example:
run 5 ms
log UUT/*
run 5 ms

In above example, simulation runs for 5 ms and all singals from UUT/* region are logged with log command.Simulation runs again for 5 ms. So after 5 ms signals with disabled logging remain visible on Accelerated Waveform Viewer. The value displayed on the waveform is equal to last value recoredded at the time point when logging was disabled.

For the log command here are some examples:

Example:
log -ports UUT/*

Traces all ports declared in the UUT design region.

Example:
log -mem -rec UUT/*

Traces recursively all signals(including Verilog memories) declared in the UUT design region.

Example:
log CLK RST

Traces the CLK and RST signals from the current region.