Which logic circuit simulator (freeware) do you recommend ? - Page 1
Forum section: electronics / beginners

author: BravoV
author_rank: Super Contributor
timestamp: June 26, 2014, 10:21:03 am
content: Just for novice design, and what I need is just to proof my logic design, and also hopefully supports the common logic ICs like 4xxx or 74xxx too.Interface and gui wise, I wish its quite similar to ltspice to reduce the learning time and effort.Prefer offline version rather than have to be online to use it.

author: free_electron
author_rank: Super Contributor
timestamp: June 26, 2014, 12:23:20 pm
content: Download an older (pre version 10.0) version of altera quartus. You can pick the oldest one you can find.Fire it upFile -> new schematicFile -> saveDouble click on the drawing area to bring up library. Simp,y type things like nand2 , 74138 , input , output , nor4 and so on, place , connect wires. Doubleclick io na,es to change them. When happy -> saveFile -> add new to project -> vector waveform file.Now, at the top menu bar there are two arrows (right pointing triangles like you would start playing music. The left one compiles, the right one fires the simulator. After a change in schematic you need to compile. Just click the left arrow and wait for comp,etion.After a first compile : in the waveform editor , left panel right-click and select import nodes.A panel opens. Simp,y click the button 'list' and throw them all in the right panel (or the ones you want to see)Then simp,y draw waveforms. Right click a signal to alter it.This software is very easy to learn.Big advantage is that, later on, you can start designing logic also with verilog or vhdl , drop that in you system and wire it up as well. And ultimately you can spit out the config file to load in an FPGA or CPLD.It has a library with almost any ttl 74xx series out there as well as many gates that don't exist. If you need a 7 input or gate simp,y place an OR7There are wizards to create all kinds of special functions like ram and rom , clock generators , arithmetic units and much much more.The software is free and exists for both windows and linux, so you can't complain there.The download is large... This is, after all, a professional tool used by logic designers to develop multimillion gate FPGA designs.

author: BravoV
author_rank: Super Contributor
timestamp: June 26, 2014, 03:16:05 pm
content: Quote from: free_electron on June 26, 2014, 12:23:20 pmThanks Vincent, I'm going to try it.Wow .. its a 961 MB downloadBtw, please verify is this the right page to download it ? ->Quartus II Subscription Edition Software Version 9.0 Service Pack 2, not the "web" edition.I'm still open to other recommendations while I'm reviewing this heavy Altera Quartus application, surely its way overkill for my novice level needs.

author: tautech
author_rank: Super Contributor
timestamp: June 26, 2014, 03:34:58 pm
content: Yes you preferred a download, but just in case you have not seen this, I have found it useful over the years:http://tams-www.informatik.uni-hamburg.de/applets/hades/webdemos/10-gates/00-gates/chapter.html

author: dentaku
author_rank: Frequent Contributor
timestamp: June 26, 2014, 10:49:59 pm
content: Have you tried logisim?http://ozark.hendrix.edu/~burch/logisim/

author: zapta
author_rank: Super Contributor
timestamp: July 03, 2014, 09:23:42 pm
content: Quote from: dentaku on June 26, 2014, 10:49:59 pmJust installed it and it's a very nice basic simulator. Compact, easy to install, multi platform support, works out of the box, extensible and easy to use. I like it.

author: sfiber
author_rank: Regular Contributor
timestamp: July 03, 2014, 09:26:57 pm
content: I recommend proteus for logic simulation.Its good at digital electronic

author: amyk
author_rank: Super Contributor
timestamp: July 04, 2014, 04:08:20 am
content: Quote from: zapta on July 03, 2014, 09:23:42 pmUnfortunately it has two limitations which are rather irritating: not all components can be rotated, and bidirectional pins on subcircuits are not supported. The former makes for messier layouts, but the latter means a ton of elaborate and impractical workarounds are needed for simulating common structures like buses since circuits don't quite behave like reality anymore.