>>> Unrelated, but tangential, How do you like LogiSim?
>>
>> Not very much.
>>
>> I mean, it *works*, but that's about it. It's really hard work to *do*
>> anything with it. All gates default to having 5 inputs, no matter how
>> many times you change it back to 2. All devices default to East
>> orientation, no matter how many times you change it. Even just moving
>> part of the circuit to make some room is quite unecessarily difficult.
> 
> Funny, it seems to get high ratings on SourceForge. ;)
> 
> But, yeah, all of your complaints are legitimate.

Too right! ;-)

> Actually, if you click 
> an item on the toolbar (And I hate the way the toolbar is tied to the 
> project, BTW...) and change its attributes there, then it should stick. 

I would literally have never thought of that.

> Pin labels on a subcircuit are a major PITA. IMO it should print the pin 
> on the block (even if the block needs to be a tiny bit larger)

That and the subcircuit label...

> One thing that is particularly annoying is if you need a gate with an 
> even number of inputs beyond 2: They don't exist.

Yeah, that too. Hello? It's software? It's not like with real hardware 
where it would *cost money* to have more sizes available. :-P

> Yeah, it doesn't do too well with latches or flip-flops. I tried to 
> build a J-K flip-flop in it, and it fell flat. Surprisingly the latch 
> worked fine (Maybe because it was a NAND latch, instead of a NOR latch?)

It's trying to be helpful by detecting circuits which are unstable.

Actually, I found a small hack: If you have, say, an RS latch and you 
configure the S pin to float low and the R pin to float high, it 
generally stops complaining. (Unless something really *is* wrong...)

> Another nuisance that I've encountered a frustratingly large amount of 
> the time is the "phantom wire"

Yeah. The whole wiring concept is just awkward. For example, Reactor 
(which has nothing to do with electronics but does involve wiring things 
together) has wires that go in a straight line from pin to pin. And when 
you move stuff, IT DOESN'T BREAK ALL THE WIRES OR RANDOMLY CONNECT THEM 
TO OTHER PINS! Sheesh, it's not rocket science...

> Also frustrating is the lack of bidirectional pins for subcircuits.

So far I haven't found this to be a problem.

> I'm not terribly concerned with how the application looks. It functions 
> reasonably if you stay away from the caveats.

I'd prefer something less ugly to look at, personally.

>> But apart from all that, it works perfectly. :-}
> 
> It does the job, at least. It's somewhat better than the rest of the 
> programs out there.

KLogic was easier to wire up. And it could do simulation graphs, which 
is extremely useful when you're trying to check, e.g., that your flip 
actually flops on the rising edge.

On the other hand, KLogic crashes constantly, and sometimes gives you 
blatently incorrect results, which is far, far worse than merely being 
difficult to use.

> One thing the program truly needs is hotkeys. The way it is now requires 
> excessive mousing.

It already *has* keyboard shortcuts for selecting different gates and 
stuff. What are you asking for?

> Falstad's circuit sim seems a bit easier to use at times, and it's 
> interface isn't stellar.

Which one?

> Heh. A side project to this whole thing is writing my own logic 
> simulator.

I also considered doing this. It would be nice to be able to concentrate 
on building logic rather than working around the limitations of some tool.

> I've got it at least moving signals from point a to point b 
> reliably. I can modify wires and move things around in the program, but 
> that's about it. My simulation model is different (from what I can tell) 
> from Logisim, so I'm guessing the whole flipping out over oscillation 
> and stopping the simulator may not happen. We'll see, but that's the 
> trouble with feedback. ;)

The reason I haven't attempted this yet is that I have literally no clue 
how to do something as complex as registering arbitrary mouse clicks and 
drawing sophisticated graphics in response. (E.g., how the hell do you 
figure out what the user just clicked on? Usually I let the toolkit sort 
that out - but this doesn't work if you draw everything yourself.)

> I have the project on SourceForge (yeah, I'm going to do the entire open 
> source thing with it. Why not?) But, contrary to their suggestions of 
> releasing files on essentially day 0, I haven't released anything yet. 
> Once I get more of the basics done, I'll do a preview release.
> 
> One of the things that would be nice is the ability to create a timing 
> graph.
> 
> I also have a design goal of allowing the interface to be flexible. Such 
> as allowing the user to assign hotkeys to items, giving a choice between 

> 
> We'll see if it turns out to be anything more than vaporware, though. I 
> have a history of ethereal personal programming projects.

Join the club. ;-)

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