Accelerated Waveform - Design Entry and Simulation Course 16 pps

16.3.1 Simulation SetupThe Accelerated Waveform and the ASDB file allow refreshing the display of simulation results while the simulation is running.. • Call the context menu and use th

Accelerated Waveform

Design Entry and

Simulation

Course 16

16.2 Overview

The Accelerated Waveform is a high performance waveform viewer

available for Active-HDL users The simulation results are stored in a

simulation database called ASDB (Aldec Simulation Database).

The Accelerated Waveform Viewer includes a number of improvements in comparison to the Standard Waveform Editor:

– The Accelerated Waveform is optimized for speed Simulation databases in excess of 1GB are loaded almost instantly, which means that large waveform files can be loaded during a few seconds Waveform scrolling and zooming is also instantaneous Large signals including Verilog memories or large VHDL records can be expanded without any delay.

– The format of the simulation database is optimized for large designs and long simulation runs File sizes are smaller in comparison with the previous version.

– Time needed to restart a simulation with a large number of signals logged is reduced dramatically.

– In the majority of test cases, a system memory needed to run simulations with full signal history logging is reduced by a factor of two or more.

– Simulations that log a full history of all signals can be several times faster over the previous version of Active-HDL.

– Arrays of real values, multidimensional arrays, and sparse memories can be observed.

16.3.1 Simulation Setup

The Accelerated Waveform and the ASDB file allow refreshing the

display of simulation results while the simulation is running The refresh

interval can be specified when the ASDB Simulation Database refresh time checkbox is selected.

16.3.2 Simulation Setup

Both options presented in the two previous slides have their equivalent switches for the asim command:

asim [-asdb [<filename>] [-asdbrefresh <time>]] <top-level>

-asdb : enables the ASDB file generation

-asdbrefresh : specifies the refresh interval

For more information, refer to the -asdb and -asdbrefresh options of the asim command in the Active-HDL On-line documentation

– If you wish to follow the operations, open the low_pass_filter design.

– Execute the compile.do macro This will compile all source files.

NOTE: Although wave command works just as well it is not recommended A warning is reported whenever wave command is issued when -asdb switch is in effect.

16.4.1 Adding Signals

• Set the circuit(circuit) entity/

architecture pair as Top-Level

Initialize Simulation.

• To start logging signals using GUI

options, switch to the Structure tab

of Design Browser.

• Select the instance in the upper part

of the Design Browser (hierarchy

tree) or particular signals in the

bottom part (local objects).

• Call the context menu and use the

Add to Accelerated Waveform

option.

This will open the Accelerated

Waveform Viewer and add the

selected signals.

16.5 Signal Grid

The Signal Grid panel can be customized to display various information about the signals:

– Database file name, – Mode (signal, input, output etc.)

– Hierarchy path – Signal name – Type

– Value – Next difference – Previous difference Signals can be sorted according

to the content of each column (except Value).

Enable the Hierarchy column

and use it to sort the signals.

16.6 Named Row

Groups and individual signals

can be separated by Named Rows A Named Row can

be created using the context menu invoked in the Signal Grid area or the keyboard shortcut (Ctrl+I) and then renamed for better legibility

16.7 Simulation Run-time Refresh

The Accelerated Waveform allows to observe the contents of the

Simulation Database while the simulation is running To utilize this functionality the simulation session has to be properly set up (slide 16.3.1)

To refresh the content of the Waveform Viewer, press the Reload Waveform button

NOTE: To refresh the signal list when additional signals have been added to the database

that is already open in the Viewer, you have to open the database again.

16.8 Multiple Waveform and List Views

The Accelerated Waveform window can be split into several Waveform or List panes To create a new Waveform View use the

button To create a new List Window click the button Drag&Drop the signals you want to observe in the newly created view

All views are synchronized i.e scrolling on the time axis in one view causes the other views to follow the position

The active view is indicated by the reddish scrollbars

To close the currently selected view, either use the context menu

option or click the Close Active View button

16.10 Cursors

An arbitrary number of cursors is available to the user A cursor can be created at any time and given a name that suits you The Accelerated Waveform displays distance between each two cursors.

Clicking a given cursor makes the cursor active (displayed in red)

– Browse by difference mark

– Browse by rising edge

16.12 Bookmarks

The bookmarks can be used to mark particular places on the waveformruler and then move the current cursor from one bookmark to another.The number of bookmarks is unlimited

Controls for bookmark navigation are:

– Toggle bookmark

– Remove all bookmarks

– Previous bookmark

– Next bookmark

16.13 Virtual Bus

Several objects can be merged into one aggregate object called Virtual Bus This option may be especially useful for combining vector elements

split during synthesis etc

To create a virtual bus, make multi-selection using mouse and Shift

and/or Ctrl key Call context menu and choose Create Virtual Bus

option (Ctrl+U) Virtual bus can be given a user-defined name

16.14 Waveform Comparison

The Accelerated Waveform provides means to compare individual signals within the same database (Compare selected ) and the entire simulation databases (Compare waveforms ).

To compare a couple of signals within the same simulation database, select two signals and use either context menu option or toolbar button and set the options

mark

16.14.1 Waveform Comparison

• To compare the entire simulation database or selected signals with the

contents of reference ASDB, use the Compare waveforms toolbar

button

• Point to the reference waveform and set the comparison options

• Click OK

Difference mark

16.15 Analog Display

The Accelerated Waveform supports analog display of signals In this

mode, signal values are treated like samples forming an analog waveform

– To enable the analog display, call the Signal Properties dialog using context menu option or use Alt+Enter key combination.

– Switch to the Display tab.

– Choose Analog in the Shape section.

– Adjust the Height.

16.16 Saving Waveforms

Although the Aldec Simulation Database file may contain an extremely large number of traced signals the user does not have to view them all.The Waveform Configuration file (.AWC) contains information about signals in the current view and their properties This file is always associated with an ASDB file

NOTE: The AWC file is only valid for

the ASDB file it was created for If

you overwrite the ASDB file, the

configuration file will not work with

the new database.

16.17 Format Conversion

The Accelerated Waveform is accompanied by a number of utilities

that perform conversion of various waveform formats from and to ASDB:– asdb -> awf

16.18 Appearance Customization

The Accelerated Waveform Viewer appearance settings can be

customized to suit the user’s visualization preferences Changes made to the colors, fonts and sizes can be then saved to a file Active-HDL installation provides 3 predefined themes that can be selected