Library for digital electrical components based on the VHDL standard with 9-valued logic and conversion to 2-,3-,4-valued logic


This library contains packages for digital electrical components. Both, type system and models are based on the VHDL standard (IEEE Std 1076-1987 VHDL, IEEE Std 1076-1993 VHDL, IEEE Std 1164 Multivalue Logic System):

The logic values are coded by integer values. The following code table is necessary for both setting of input and interpreting the output values.

Code Table:

Logic value Integer code Meaning
'U' 1 Uninitialized
'X' 2 Forcing Unknown
'0' 3 Forcing 0
'1' 4 Forcing 1
'Z' 5 High Impedance
'W' 6 Weak Unknown
'L' 7 Weak 0
'H' 8 Weak 1
'-' 9 Do not care

The library will be developed in two main steps. The first step contains the basic components and the gates. In the next step the more complicated devices will be added. Currently the first step of the library is implemented and released for public use.

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This Modelica package is free software and the use is completely at your own risk; it can be redistributed and/or modified under the terms of the Modelica License 2. For license conditions (including the disclaimer of warranty) see Modelica.UsersGuide.ModelicaLicense2 or visit

Extends from Modelica.Icons.Package (Icon for standard packages).

Package Content

Name Description
Modelica.Electrical.Digital.UsersGuide UsersGuide User's Guide
Modelica.Electrical.Digital.Examples Examples Examples that demonstrate the usage of the Digital electrical components
Modelica.Electrical.Digital.Interfaces Interfaces Basic definitions
Modelica.Electrical.Digital.Tables Tables Truth tables for all components of package Digital
Modelica.Electrical.Digital.Delay Delay Delay blocks
Modelica.Electrical.Digital.Basic Basic Basic logic blocks without delays
Modelica.Electrical.Digital.Gates Gates Logic gates including delays
Modelica.Electrical.Digital.Sources Sources Time-dependent digital signal sources
Modelica.Electrical.Digital.Converters Converters Converters between 2-,3-,4- and 9-valued logic
Modelica.Electrical.Digital.Registers Registers Registers with N-bit input data and output data
Modelica.Electrical.Digital.Tristates Tristates Transfergates, Buffers, Inverters, and WiredX
Modelica.Electrical.Digital.Memories Memories  
Modelica.Electrical.Digital.Multiplexers Multiplexers  
Automatically generated Tue Apr 05 09:36:17 2016.