R001 VCD Reader

Outline

Value Change Dump (VCD) is an ASCII-based format for dump files generated by EDA logic simulation tools.

Platforms

32/64bit

Requirements:

None

Known limitation:s

File size limited by virtual memory and temporary storage

Status:

Stable

Operations:

Load
Stream

Parameters:

SystemC Hierarchy Resolver: Enables to build scope hierarchy from SystemC names.

Configuration:

Default Serializer Configuration with modified paramters.

Features:

Vector signals are getting combined (v[0], v[1] -> v[0,1])
9 state logic supported (not just 4)
TIMEZERO command supported
String signal support (need to be defined as string (not real) in the vcd header)

Video

Screen Cast: Using the VCD and Analog Tabular (TAB) Reader

About the Value Change Dump (VCD)

The VCD file includes a header section with date, simulator, and time scale information, a variable definition section, and a value change section in that order. The sections are not explicitly described within the file, but are identified by the inclusion of keywords associated with each section.

    $date
   Date text. For example: November 11, 2009.
$end
$version
   VCD generator tool version info text.
$end
$comment
   Any comment text.
$end
$timescale 1ps $end
$scope module logic $end
$var wire 8 # data $end
$var wire 1 $ data_valid $end
$var wire 1 % en $end
$var wire 1 & rx_en $end
$var wire 1 ' tx_en $end
$var wire 1 ( empty $end
$var wire 1 ) underrun $end
$upscope $end
$enddefinitions $end
$dumpvars
bxxxxxxxx #
x$
0%
x&
x'
1(
0)
$end
#0
b10000001 #
0$
1%
0&

Usage

The VCD reader can be used to open workspace resources and together with ports (direct connection to the target using TCP, Serial, J-Link, ...).

Configuration

You can modify the reader behavior under Preferences->impulse->Serializer->VCD:

You may modify the default parameters (see "Default Parameters");
You may add a default serializer configurations and modify its parameters. Then you can select between multiple configurations (containing different parameter sets) when using the serializer.

Parse errors

The reader will provide a parse error message if the input can not be read. The message usually contains the error position, the reason for the failure and a stack trace.

If you can not resolve the problem (e.g. obvious format error in the input file), please send this message together with the input file to "This email address is being protected from spambots. You need JavaScript enabled to view it.".

	Reader: de.toem.impulse.serializer.xyz 
	Error at position: 4800
	Text at position: "o !.
	Up
	Uq
	Ur"
	Message: Invalid character
	Type: class de.toem.impulse.serializer.ParseException
	Stack trace: 
	
	de.toem.impulse.serializer.xyz.xyzReader.parse(XYZReader.java:459)
	de.toem.impulse.serializer.xyz.xyzReader.parse(xyzReader.java:363)
	de.toem.impulse.serializer.xyz.xyzReader.read(xyzReader.java:269)
	de.toem.impulse.serializer.xyz.xyzReader.read(xyzReader.java:237)
	de.toem.pattern.element.Element$1.execute(Element.java:1063)
	de.toem.eclipse.hooks.actives.EclipseActives$3.run(EclipseActives.java:73)