The Node

Posts Tagged ‘review’

I don’t usually do reviews here at The Node, but in this case I’m going to make an exception. I’d bought an Arduino micro-controller board a while back but found out that while it was pretty easy to learn in terms of programming the thing, I didn’t know enough about basic electronics to do exciting things with it. While I have done a bit of prototyping of simple circuits on breadboards, I was more interested in learning the fundamentals and playing around with basic components without risking the hardware I had.
So I dutifully went to Google and typed in “circuit simulator” figuring that hey, I’ve read a couple of books on electronics. Components and current and voltage should be easy to simulate on a computer, right? There must be loads of these types of applications available!

Well, yes. Obtuse pieces of specialised industrial software called things like SPICE and Qucs. While I was pleased to see they were open source efforts, they didn’t really seem to do what I wanted – or at least not easily. When you think of “circuit simulator”, do you think of easily accessible components you can drag and drop onto a virtual workspace? Do you not almost expect to be able to snap everything together with virtual wire and connect to a virtual power source and see your circuit simulation in action? I did, and these seemingly professionally-used applications just weren’t user-friendly enough for a beginner to be able to do that. And considering the way that circuits operate, it was well….weird.

Well, I found that app on Android almost by accident. It’s called EveryCircuit and it’s much easier to use that any other circuit simulator on any platform.

It acts just as you’d expect really, which seems somewhat radical compared to almost any other circuit simulation software I’ve come across. You have a list of standard symbols of components at the top which you can flick through with your finger and a workspace to drag and drop your components. Most components have a radial dial to change the values of the components such as resistance or you can type the values in manually.
You connect your power source, either AC or DC and press the ‘play’ button. You’ll see the voltage drop across components, how many milliamps are flowing through the circuit and so on. Below is my real circuit design for a door alarm that activates when the door is left open.

[Yes, I know the power wastage is too high in the non-activated state :-)]

It’s certainly made me more confident about prototyping simple circuits before I reach for the breadboard and the app is well worth the money at £6.00. The general design is solid. While this app is fully usable on a phone (I am using it on a Nexus S running ICS 4.0.3), I imagine it was designed for an Android tablet in mind. This is clear of the lack of zoom functionality as you cannot “pinch” the screen to zoom in or out, which was sort of a pain…especially with larger circuits. The component list at the top has no “tooltips” to say what the symbol for each component means which will not be a problem for experiencing electronics hobbyists but is annoying for a beginner like me. I also discovered that I couldn’t simulate just any circuit diagram I found on the web…especially ones that included polarised capacitors as the app only has general capacitors. Again, I’m not sure if this was me or the app – do polarised capacitors matter? Don’t really know yet. EveryCircuit does seem to be updated on a regular basis, so I imagine more and more components will be added over time. It would be nice to have several common integrated circuits (ICs) included such as the 555 timer which a lot of simple circuits and educational and hobby texts make use of. One of the things that EveryCircuit does do well is the ability to change the values of components and see the immediate difference in the running simulation which is really great and helps you make sense of what is going on.

Liked:

- Works just like you’d expect a circuit simulator to work (finally!). Extremely intuitive interface.
- Includes it’s own fully functional oscilloscope for AC circuits.
- Reasonably wide range of common components to play with.
- Running simulations are interactive and include a lot of real-time information.
- The developer is extremely approachable and helpful with queries and questions.
- Basic integration with ElectroDroid, another handy Android electronics tool.
- You can email your designs as a JPEG to anybody from within the app or export via regular Android sharing services. This includes the circuit design in simulation mode.

Disliked:

- If you’re a beginner in electronics, there’s no help or information about what the circuit symbols for each component are.
- No zoom feature, especially notable in it’s absence on a phone rather than a tablet.
- Would be nice to have more components available like polarised capacitors, buzzers, variable resistors and a selection of common ICs.
- Transistors have a value attached to them which you can change, but no explanation of what that values does and no circuit diagram seems to mention a transistor value. This adds an element of doubt to a beginner about whether the app is wrong or you are when things don’t work. Disconcerting. A help page and basic user-guide would help alleviate these doubts.
- Modifying the connectors between components can sometimes be a frustrating experience and you often have no option but to delete many at once. This can sometimes lead to confusing circuit layouts as you cannot change the the layout of the connections from one component to another.
- No ability to change the colour-scheme for printer-friendly diagram exports.
- A little too easy to overwrite saved designs. An “are you sure?” dialog box would save the day here.
- More simple DC circuit examples for common entry-level tasks would be most welcome for the newbie.

EveryCircuit is a definite must for any electronics hobbyist or professional. I was amazed that I, as a relative beginner, could actually prototype and test a circuit within minutes. With a little more work on the interface and a wider selection of components, it could probably be sold to schools and colleges as a full-blown educational product. It’s certainly easier to use than anything else I’ve been able to find, on Android or any other platform. I would also mention that I would pay a fair bit of coin to get a desktop version of this app for my PC. Either that, or I’m going to have to get an Android tablet!

Conclusion: If you’re into electronics at all, you need this app. More components and some interface tweaks will make this app the hobbyists holy grail.

Update 27/03/2012: The author has contacted me to state that there is, in fact, a “new workspace” option. There is a “New” button in the “Open file” dialog that clears the workspace and allows you to start over. The review has been updated accordingly.

EveryCircuit is available on Google Play here.

Fedora 15 is the first Linux distribution to ship with the new GNOME 3.0 user interface. This is what most Linux distributions barring Ubuntu will no doubt be using in the near future so it’s pretty important.

I’ve used Fedora 15 on the desktop for a couple of weeks now. I was expecting to love it, mainly because although I wasn’t all that taken with Ubuntu’s new Unity interface, I didn’t hate it as passionately as some. And hey….different isn’t necessarily bad, right?

Right?

This is so frustrating. I’ve been using Fedora since version 6 and I much prefer the actual “Linux” side of it to Debian-based distros. You’re reading this right now on a Fedora 15 server, for example. The GUI side has always been pretty “meh” but Canonical really showed how damned old everything looked. It was high time the GUI was overhauled and Ubuntu – regardless of how you feel about the Unity interface – pretty much paved the way. GNOME was conceived when Windows 95 was the height of UI design, and simple subtraction will tell you that was a long time ago.
So great, GNOME 3.0 with a completely – some might say radically – new interface.
The good is that it’s Fedora Linux. That is to say, it’s Red Hat underneath and I’ve always used Red Hat since version 6.0 so I’m comfortable with it. As a server it’s still as fine as it ever was. The only jolt so far being the new systemd init daemon rather than the more traditional sysvinit. This will take some getting used to, but for now the compatibility layer (which I assume is there) shields you from most of the shock. It’s still disconcerting to not have a ‘/etc/inittab’ file, however.
But none of this really matters – Linux is a proven technology on the server and is likely to remain so. So that leaves the desktop which frankly, I’ve not used since Fedora 12.
Now, if Fedora 15 was actually bad, I wouldn’t be so frustrated. The reason being that GNOME 3.0 is great. It’s slick and the new interface paradigm is also great.

Or at least it would be if the Fedora team had finished it.

That’s my beef here. Fedora 15 has shipped with a broken interface. The sweet, gooey command-line centre is fine, but GNOME 3.0 is unfinished….visibly unfinished. For example, the main interface bar at the top is a tasteful dark colour. The dialog boxes and windows on the other hand are lifted straight from GNOME 2.3, complete with light-grey colours and big, blocky icons.
I really harshed on the Linux Action Show guys for slating Fedora 15 from the angle they did and, while I don’t share their ire with the Fedora distribution in general (Debian fanboys, natch :-)), they were spot on about GNOME 3.0.
Dialog border colours don’t match, things are labelled inconsistently or badly. Lots of little things that in isolation wouldn’t be a big deal but they mount up quickly. Using Fedora 15 as a desktop system is a little like being flogged to death by silk bootlaces. You can set terminal windows to be transparent, but it doesn’t seem to work because of the new desktop. The design team didn’t seem to know where to display mounted volumes. Streaming a video under VLC from a sever is smooth on Ubuntu 10.10 but buffers frequently on Fedora 15. The list goes on.

The really annoying thing is what does work in GNOME 3.0 works really well. The overall philosophy is much more integrated than Unity is – indeed it makes it seem positively bright and clunky like spit-covered Duplo blocks. The “log off” dialog box looks really cool and you wish the rest of the dialog boxes looked that way, yet they don’t. The way the desktop zooms out rather than the use of work-spaces is brilliant, especially as all the windows are still non-modal and visibly running. Why bother re-sizing windows when you can do that? Inspired.

It’s bewildering that some things are so great and others so clearly not. In using it, you sometimes catch glimpses of the future and I imagine Fedora 16 will be great. The question is, why release this? It’s open source, has no stockholders to answer to and doesn’t need to turn a profit. The mystery isn’t why Fedora 15 is broken, I get that…they just didn’t have time to finish. The real mystery is why release something so obviously and clearly unfinished at all? Not broken as such but certainly not ready to hit the FTP servers. If I had been in charge and I had used this, I would have said “not for another six months, fellas”. Why stick to a firm six-month release cycle if you’re just going to put out occasionally dubious releases? Why not wait a couple of months. I’d have been just as happy to use Fedora 15 in September.

If you’re using Fedora on a server – go for it. The new dynamic firewall looks interesting and systemd appears to be far more versatile than sysvinit and you’ll get all the regular package upgrades and it’s stable as it ever was. But on the desktop? Not yet.

But probably soon :-) Say, in another six months. As they say, one to watch.

Sorry for the 24 hour outage – I was upgrading the server from Fedora 14 to Fedora 15. I don’t really see what all the shouting is about, but then I don’t use a GUI on that machine so no real impression of how GNOME 3.0 shell is, certainly nothing compared to the guys over at The Linux Action Show, who piled on the hurt. Somebody else over on Reddit was waiting for the review from the Linux Outlaws, but somebody else pointed out that Fab is now part of the Fedora Project and “will totally be biased” :-) I’ve not listened to that episode yet, so we’ll see. I’ll probably install Fedora 15 on a spare laptop and see what it’s like.
The most marked difference for me so far when tweaking the configuration on the server was the use of systemd as the init daemon rather than the more usual sysvinit. I’ve heard that it has a new dynamic firewall as well which I’ll probably look into. Overall, I don’t see what the fuss is about. My system is faster and copes with tweaking in a logical manner. However, Linux is no longer just about the server as Ubuntu has proved, so distributions these days live or die by their GUI. It’s interesting that we seem to be facing a bit of a paradigm-shift in GUI design lately. Canonical has Unity, I guess the rest will go to GNOME 3.0 when it’s matured. The catalyst for this is clearly because of smartphones. Even crusty old Windows in getting in on the action with a frankly eyebrow-raising demo of the new Windows 8 GUI.

It’ll take a while to work out what systemd is all about though. As far as I can tell, instead of having the familiar run levels (commonly 3 or 5), systemd has the concept of ‘targets’. So this means there is no ‘/etc/inittab’ file which was kind of weird to be honest. Instead of setting the run level…sorry target…via the inittab, you create a symbolic link from ‘/etc/systemd/system/default.target
‘ to either:-

/lib/systemd/system/multi-user.target – which is equal to run level 3

or…

/lib/systemd/system/graphical.target – which is equal to run level 5

So…

ln -s /lib/systemd/system/[target name].target /etc/systemd/system/default.target

…is the same as setting the default inittab run level. Seems a little complex but based on the documentation, it appears that instead of being limited to run levels 0 to 6 which were hard-wired into the sysvinit daemon and formed a basic part of the UNIX-like structure, you can pretty much create your own custom targets. This would certainly be very flexible. You would have much finer grain control over what functionality was available in each target mode and you could create as many targets as you liked. At least, that is what the little documentation I’ve read about it seems to imply.

So anyway, I’ve added a little love(lock) to The Node. More stuff soon.

My father died earlier this year. The reason that I mention this is because back in the early eighties, my father (being a bit of a gadget freak himself) was one of the first people I knew to get a Betamax video recorder. I used to see him at weekends and he would get various pirated videos of movies that he thought I might like – usually science fiction stuff like WarGames, Superman, Star Wars, The Terminator, Aliens and the like. I’ve him to thank for my interest in science fiction, computers and programming. A large part of this was due to Tron, a Disney film from 1982.

For those of you who haven’t seen the original, it’s about a hotshot programmer called Kevin Flynn who was fired from ENCOM, a slightly vague software and technology company, for being a security threat. The reason for this was that Ed Dillinger, the now CEO of ENCOM, stole five of his videogames from the ENCOM mainframe and passed them off as his own, thus getting himself promoted to CEO in the process. Flynn, now running an arcade has been trying to hack into ENCOM using one of his own programs called Clu to get evidence of Dillinger’s wrongdoing and get himself vindicated. Alan Bradley, another employee is vexed that his security clearance has been temporarily shutdown as he was working on a program called Tron, a security program that “monitors all activity between our system and other systems – it finds any activity that isn’t scheduled and shuts it down”. Dillinger is dismayed by this, as the corporation is actually under the control of MCP – the Master Control Program, a rougue artificial intelligence that Dillinger once wrote as a chess program. Dillinger suffers the MCP’s rule at ENCOM due to the MCP threatening to expose Dillinger’s theft of Flynn’s videogames to the world. Flynn along with Alan and his ex-girlfriend eventually decide to team up and break into ENCOM. In the process, Flynn gets transported into the ENCOM mainframe by the MCP where he finds out that all the videogame and other programs are actually anthropomorphic representations of their programmers (referred to as Users in the digital world and revered by the Programs as gods) and videogames themselves take on a terrifying life or death aspect. Aided by the Tron program, Flynn seeks to break the MCP’s hold on the system and get evidence of Dillinger’s theft.
This was pretty cutting edge stuff in 1982, where there was no Internet and hardly anybody owned a personal computer outside of geeks and a few children. Not only that, Tron was one of the first movies to use actual computer graphics for some of it’s special effects, including the famous Lightcycle chases. It utterly grabbed my eight-year old mind and got me interested in programming. Tron was one of the gifts that my father exposed me to as a child. As he died in March, I wanted to see the sequel Tron Legacy, before the year was out as a fitting send off to my dad and all that I am because of him.

Much has changed in 28 years – both in the world of Tron and real life. Smartphones, the Internet, Twitter, netbooks…all these things were unheard of when the original Tron came out. In the film, Kevin Flynn became the new head of ENCOM and had a son, Sam. One day in 1989, he simply vanishes and Sam grows up under the care of his grandparents and Alan Bradley Flynn’s friend and colleague. Now a young adult himself and the largest shareholder of ENCOM, Sam is embittered by the loss of his father and the direction that ENCOM has taken – it’s pretty much Microsoft at this point. Eventually he goes to his father’s old arcade hall downtown and discovers the truth – the Grid, a virtual environment that Flynn created is real and Flynn has been stuck inside all these years, betrayed by Clu 2.0 who wanted to create a “perfect system”. The Grid has been evolving independent of the Internet for all these years (running SolarisOS I noticed!) and Clu has been corrupting Tron and all the other programs to his will.
The graphics of this new world are certainly what you’d expect from 2010 and some old favourites like the Disc battles and Lightcycle games have been updated to reflect modern sensibilities. Flynn has become something of a digital mystic, living in exile on the outskirts of the Grid. The reunion between father and son is touching, helped along by an excellent soundtrack by Daft Punk. The story is a little off in places though which makes the film so much less than it could have been. The problem is that the digital world of the original Tron was not made on purpose to be a virtual environment, it simply was the result of the programs and technologies that were written, unknown and unfelt by their creators, the programmers. Here, the Grid is a true virtual environment created on purpose by Flynn…yet it serves no real purpose but to be his digital playground until Clu betrays him and traps him inside. It is a subtle shift of focus and one that I think shows a major misunderstanding of the intent of the original. It’s not exactly bad and the effects are certainly amazing – it just felt a little off in parts. To be fair, the original story wasn’t brilliant, so I wasn’t expecting too much – but I did expect a slightly better understanding of the source material and the whys and wherefores of the virtual world and the reason it exists at all.

That said, I enjoyed it immensely and it looks as though (if this one does well) that we’ll get a sequel. I have to admit, I saw many parallels with the events of the past year within Tron Legacy and I simply wish my father had been here to see it with me. In that sense, the movie succeeds for me and brings a certain closure to my childhood. Thanks Dad…for everything. I think Sam Flynn would say the same.