Digital Logic & Design Fundamentals — Installation

What You're Setting Up

This guide's Boolean simplifications are hand-verifiable by truth table, and Overview's own examples are already "verified computationally against all N input combinations" — this section sets up the two tools that make that pattern real: a small Python truth-table checker (the exact technique Overview's examples use, now as a reusable tool), and Logisim Evolution, a free circuit simulator for actually building and testing gate circuits visually.

Install Python

bash

python3 --version

No extra packages needed — a truth-table checker over a handful of Boolean variables is simple enough for plain Python, no NumPy required.

Verify Your Setup — Recompute Overview's Boolean Simplification

This reproduces Overview's worked simplification (F = AB + AB' + A'B, simplifying to A + B) as an exhaustive, programmatic truth-table check.

python

import itertools

def f_original(A, B):
    return (A and B) or (A and not B) or (not A and B)

def f_simplified(A, B):
    return A or B

print("A B | original simplified match")
for A, B in itertools.product([0, 1], repeat=2):
    orig = int(f_original(A, B))
    simp = int(f_simplified(A, B))
    print(f"{A} {B} |    {orig}         {simp}       {orig == simp}")

Expected output — all 4 rows should show match=True:
A B | original simplified match
0 0 |    0         0       True
0 1 |    1         1       True
1 0 |    1         1       True
1 1 |    1         1       True

Matches Overview's claim exactly — the 3-term original and the
1-term simplified expression produce identical outputs across every
possible input, confirming the simplification is correct, not just
plausible-looking algebra.

A Second Check — the Try It Consensus Theorem Example

Reproducing Overview's Try It exercise (F = AB + A'C + BC simplifying to AB + A'C, with the BC term proven redundant) as a second, independent, 8-row check:

python

def g_original(A, B, C):
    return (A and B) or (not A and C) or (B and C)

def g_simplified(A, B, C):
    return (A and B) or (not A and C)

print("A B C | original simplified match")
for A, B, C in itertools.product([0, 1], repeat=3):
    orig = int(g_original(A, B, C))
    simp = int(g_simplified(A, B, C))
    print(f"{A} {B} {C} |    {orig}         {simp}       {orig == simp}")

Expected output: all 8 rows show match=True — confirming the BC term
is genuinely redundant across every one of the 8 possible input
combinations, exactly as Overview's Try It answer claims.

Install Logisim Evolution for Visual Circuit Building

Logisim Evolution is a free, actively maintained circuit design and simulation tool — build the actual AND/OR/NOT gate circuits from Overview visually, wire them together, and simulate real signal behavior, rather than only checking truth tables in Python.

bash

# Requires Java 21 or newer
java -version

# Download the current release for your OS from the official
# GitHub repository:
# https://github.com/logisim-evolution/logisim-evolution/releases

(needs verification — recheck against current source: exact current release version and Java version requirement change with each release — confirm both at the GitHub releases page above before downloading.)

Important naming note: search results for "Logisim" (without "Evolution") often surface the original Logisim project by Carl Burch, which ceased active maintenance around 2014. Logisim Evolution is the actively maintained successor (maintained by REDS Institute, HEIG-VD) and is the correct, current tool to install — if a tutorial or download link references plain "Logisim," confirm it's actually pointing at Logisim Evolution before using it.

Verify Everything Works

bash

# 1. Confirm the Boolean-simplification check prints match=True for
#    all 4 rows

# 2. Confirm the consensus-theorem check prints match=True for all
#    8 rows

# 3. Open Logisim Evolution, build a simple AND-OR-NOT circuit
#    implementing F = A + B (Overview's simplified result), wire up
#    input toggles and an output indicator, and confirm it produces
#    the same 4-row truth table as the Python check above

Common Setup Issues

Python truth-table check shows match=False for at least one row

This means the "simplified" expression you're testing is NOT actually equivalent to the original — treat this as the check correctly catching an invalid simplification, not a script bug. Re-derive the simplification algebraically and re-run the check rather than assuming the checker is wrong.

Logisim Evolution won't launch after installing

Confirm your Java version meets the current requirement (java -version) — Logisim Evolution is a Java application and the most common launch failure is an outdated or missing Java runtime, not a corrupted download.

Downloaded "Logisim" (not Evolution) and it looks outdated or unmaintained

This is expected — the original Logisim project stopped active maintenance around 2014. Uninstall it and get Logisim Evolution from the link above instead; the two are easy to confuse by name, but only one is currently maintained.

What's Set Up

•Python 3 — for exhaustive truth-table verification of Boolean simplifications throughout this guide

•Logisim Evolution — for building and simulating real gate circuits visually

Next Steps

Go to the Fundamentals section to continue with number systems and more advanced gate combinations (K-maps, combinational circuit design), using the same verification tools set up here.