Learn LOGICS
How each tool works, step by step — from your first project to wiring a 74LS00 on a breadboard.
The four tools
LOGICS is built around one idea: a Boolean function is the same thing whether you write it, tabulate it, map it, draw it or wire it. Three of the tools are simulators that look at it from a different side; the fourth, the Problem Generator, is for practice: it sets the problem and works your answer through.
A typical path: work the logic out in Logic Gate Simulator (or practise it in Problem Generator), then plan the physical build in Breadboard Simulator. Circuit Simulator runs a whole circuit — several outputs, displays and all — before it goes on a board.
Your first project
A project keeps everything you make for one lab, assignment or idea together, across all four tools.
- Create it. On the dashboard, press New project, give it a name (and a description if you like), then Create project. You land on its page.
- Open a tool from it. Each tool has a card on the project page. Open Logic Gate Simulator in this project opens the tool with the project attached — its name appears at the top right of the tool.
- Save something. In Logic Gate Simulator, type an expression, name it in the Saved panel and press Save. The panel says in this project.
- Switch tools without leaving. Open Tools at the top right and pick Breadboard Simulator. It opens in the same project.
- Come back to it. The project page lists everything saved in it, tool by tool. Click an item to reopen it where it was made.
Tip. A tool opened where nothing is saved yet starts on a worked example — a majority vote, a NAND gate lighting an LED, the first digit of the decoder. It is a template: nothing is saved until you change it, and then it is saved like any other work.
Projects and saving
| Tool | What it saves | When |
|---|---|---|
| Logic Gate Simulator | Named functions (the expression and its variable count) | When you press Save |
| Problem Generator | Named problems (seed, difficulty, scenario and paths) | When you press Save |
| Circuit Simulator | Whole designs: every component, wire and switch position | By itself, a couple of seconds after each change |
| Breadboard Simulator | Whole boards, the same way | By itself, a couple of seconds after each change |
Opened from a project, a tool saves into that project, kept by the server under your account, and you can reach it from any device you sign in on.
Opened on its own (from the dashboard's Tools list), a tool saves the way it always has: Breadboard Simulator and Circuit Simulator into the designs/ folder when you are on the computer running the server, otherwise in this browser; Logic Gate Simulator and Problem Generator in this browser. The dashboard lists those under Saved outside a project.
Rename or delete a project from its page with Edit details and Delete project. A deleted project goes to the server's trash, not straight to nothing.
Moving between tools
- Tools, at the top right of every tool, lists all four and the dashboard. Inside a project, every link keeps the project.
- The project chip beside it shows the project's name. Click it to go back to the project page.
- Your profile icon opens a small menu: Dashboard, Profile & account and Sign out.
- On the dashboard and the other account pages, the bar along the top has Dashboard, Projects, Learn, Plans and Profile.
A worked example
This is the sample problem from Problem Generator (seed 48213), solved the way the walkthrough asks for it.
A greenhouse controller switches on the exhaust fan when the heater is running and the roof vents are closed, or whenever the humidity alarm trips. The controller box is painted blue, sits beside 40 tomato plants, and is checked by the caretaker every morning. Design the logic for the fan.
- Sort out what is really a signal. The fan is the output. The heater, the vents and the alarm decide it. The paint, the plants and the caretaker are scenery — they change nothing.
- Name the variables. H = heater running, V = roof vents open, M = humidity alarm tripped, F = fan on.
- Translate each clause. "Heater running and vents closed" is H·V′. "Or whenever the alarm trips" is + M.
- Fill in the truth table. Three inputs give 2³ = 8 rows; F is 1 on rows 1, 3, 4, 5 and 7 (reading H V M as a binary number).
- List the minterms. F = Σm(1, 3, 4, 5, 7) = H′V′M + H′VM + HV′M′ + HV′M + HVM.
- Group the ones on the K-map. The four cells with M = 1 make one group; HV′ makes a pair.
- Write the minimized expression. One product per group: F = M + HV′. Five terms become two.
- Count the cost. One NOT (for V′), one AND and one OR.
- Build it. Your answer is tested on all 8 rows, not matched to wording: call the vents C for "closed" and F = M + HC passes too.
Who LOGICS is for
- Students taking a digital logic course — homework, quizzes and lab projects.
- Lab groups planning a build before touching a breadboard: chip count, package list, wiring plan, current draw.
- Instructors and TAs — an endless supply of quiz-shaped problems with worked answer keys. Share one seed and the whole class gets the identical problem.
- Self-learners coming to digital logic from electronics or software.