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Comment White noise channel (Score 1) 202

If you have point to point communication, traffic analysis can easily detect the participants of a network. If you have a central server with lots of uninvolved people, you either need to get the information from the server or rely on timing analysis. The timing is useless with asynchronous communication and can be obfuscated by introducing delays.

Comment Re:Photoshop (Score 1) 889

Reminds me of the time I tried to batch-convert hundreds of icons. GIMP is scriptable. So I looked at Scheme and then at the API and examples. Scheme wasn't the issue, but the API just didn't seem to make sense. After a few hours, I gave up and started Photoshop. I pressed record, converted an icon and applied the recorded script to the folder within a few minutes.

Comment Re:Cyclists DON'T obey the law! (Score 2) 696

I have yet to meet a motorist who stricly adheres to the speed limits. Or one who doesn't run a yellow light even though he could stop safely. Motorists seem to be very aware of the rules that bicyclists are breaking while they shrug off their own lawlessness as both normal and acceptable. At the same time, motorists kill thousands of people per year in the US alone and are most often at fault when a bicyclist gets hurt.

Comment Re:Cyclists DON'T obey the law! (Score 4, Insightful) 696

Bicyclists should wait at red lights just like everyone else, for example. It doesn't mean "stop, look, then proceed if you don't see a car crossing". It means you wait until it turns green.

Why? You make an assertion without providing a reason. Starting at the same time as cars exposes bicyclists to the risk of both right hooks and left hooks. Fully stoppimg also means that the bike is longer on the crossroads. If the crossing road is obviously clear of traffic, it can be safer to run the light. At least thats what a study conducted in Paris concluded. As a result, bicyclists are now explicitly allowed to run red lights at a few marked crossings.

Comment Re:old clunky junk (Score 1) 170

From a hobbyist perspective, building that board is very hard.

The thing is, it really isn't. Assuming you're wiring things up on a breadboard, what you do is:

  • Put the AVR on the breadboard
  • Temporarily wire up an Arduino as a bootstrap programmer, and use the appropriate sketch to flash the bootloader onto your target AVR
  • Connect 5V and GND
  • Plug in a quartz crystal (if needed) to the xtal pins
  • Connect a USB to serial dongle/adapter to the serial pins
  • Done.

Sure, it's a couple more steps than "Connect Arduino to USB", but it's fewer steps than the average project requires for everything else.

Comment Re:old clunky junk (Score 1) 170

Yes, I was thinking of the Gameduino shield - it's completely silly. It even has a coprocessor inside the FPGA that is user-programmable and runs much faster than the Arduino. The SPI interface is a stupid bottleneck. It would make a lot more sense if they hadn't jumped on the Arduino shield bandwagon and instead had implemented it as a stand-alone product with its own CPU core (which could just as well use the Arduino libs if they'd wanted; it wouldn't require FPGA knowledge either).

Think about it - the Gameduino is the same idea as taking a modern GPU and connecting it to a 386 through the serial port.

Comment Re:old clunky junk (Score 1) 170

I agree that if you're just plugging shields together and if you don't care about size or cost and if you're not building any custom electronics then the Arduino makes sense, even in production.

But really, I'm not focusing on commercial production here, I'm talking about hobbyists. Not those plugging in shields, but those designing their own. And making their own widgets using the Arduino as a base for their own custom electronics design. Often, people who are already designing their own boards, or at least doing permanent soldered together prototypes. People who by all measures are capable of throwing together a bare AVR... they just don't know it. Or people who randomly decide to make something useful and do a small run, perhaps still assembled by them but building more than a couple of units, and are too scared to learn how to route a tiny board with a micro and whatever else they need on it, because they don't realize just how easy it is. There is a very significant cargo cult culture here.

Code-wise, it is perfectly possible to use the Arduino libraries and software ecosystem with bare chips. That's also something that many people don't realize.

Comment Re:old clunky junk (Score 1) 170

So what are you plugging into the Arduino?

I'm not talking about the person who is still at the plug-shields-together stage and doesn't really know how to put more than 4 parts on a breadboard. Nor am I talking about some kind of custom solutions consultant who really doesn't care about efficiency and just wants to deliver the product ASAP with a minimum of effort and doesn't need it to be cost-optimized.

I'm talking about curious makers who start building things on top of the Arduino platform, understand basic digital electronics... but then somehow never move on from basing everything around the Arduino board, and think there is some kind of magical pixie dust in there and that running a bare chip is rocket science. Of which there unfortunately are a lot. People somehow end up doing truly interesting/novel designs that still have a "here goes the arduino" mentality as if it were some kind of religion.

Comment Re:old clunky junk (Score 1) 170

So, the FPGA shield is not as stupid as it could feel.

The dumb part is that you can stick an AVR-compatible core in the FPGA itself and skip the Arduino. Basically, an FPGA shield for an Arduino makes no sense when you could have a standalone FPGA board that is also Arduino-compatible by virtue of embedding an Arduino clone inside the FPGA itself. That would be a much better way of jumping on the bandwagon without doing something that is, design-wise, completely silly. It would run faster than a real AVR too.

Even if you can program a microcontroller in assembler, using direct port access, don't forget that not everyone can/want to do it. Arduino is often used by people who can barely program but need some way to sequence things (artists for example).

There's a threshold here. If you're using Arduino + off-the-shelf shields as a platform and not actually learning electronics, that's fine. That's a different story. Nobody expects you to roll your own board if you care more about the software or artistic side and don't care about the hardware.

But if you're using an Arduino and building your own designs around it, i.e. understand how to use the "black box" that is the Arduino and how to interface with it, then you really need to stop thinking about it as a black box and realize that you can just as well build your own design around a microcontroller, possibly the same one and using the same exact software initially. And then you have many more possibilities than you did when you were limiting yourself to off-the-shelf devboards.

Someone who makes a led blink under arduino has learned the basics of loop and sequence of instructions... Shields and other will help to go further...

Nothing wrong with that either. Again, to clarify, I'm talking about people who inexplicably learn enough about electronics to make their own designs around the Arduino yet refuse to ever touch a bare microcontroller for some reason, or anything that doesn't have the Arduino label on it. If you're just using off the shelf blocks and focusing on the software or using it as a beginner's learning tool then there is nothing wrong with that. I'm not saying Arduino should cease to exist or has no purpose. I'm saying there is a sizable segment of the maker community who inexplicably revere it like it's the be-all-end-all of hobby electronics and don't understand just how irrelevant it becomes after you learn the very basics of building your own hardware.

But it's also true that the number of available chips is huge and selecting one may feel difficult (mostly when only basic functionalities are needed) So I can understand that people will end up stocking one or two "generic" models and stick to them.

I was in that situation too, using the 16F84. And then one day I figured out that I could literally just go to the Microchip parts selector, plug in what features I needed, and pick the cheapest chip that fit the bill (or throw a few more things in just in case). I think one thing that is sorely lacking is documentation/tutorials on "from-scratch" circuit design - such as how to select a microcontroller from the thousands available.

But there is also the fact that the authors of learning material need to stop sticking to ancient crap. For example, the PIC16F88 was a fine replacement for the PIC16F84 when it came out (2003), with a lot more features in the same form factor for cheaper. There was literally no excuse to use the 16F84 ever in any new design or new educational material after that (there were other chips before it that fit the bill too, that's just the one that comes to mind and one that I used a lot myself). The people building the tools, devkits, and writing the docs need to start actually using devices that are current as of the time they make their design.

Now, sticking to families that you know is more reasonable, because there are many unknowns in jumping to a new chip family and you have to be willing to re-learn a lot of details. But moving between chips in the same family should be one of the things we teach anyone building their own circuits.

Arduino nano compatible bought from China end up very cheap with USB, voltage regulator, quartz... If you buy some quantity, you may drop below 1.75$/module. And the module is not much bigger than a DIP40... so yes, Arduino is a viable option at least for medium-sized production.

But... why? Why use a module when you can just stick the AVR right on your board and get a lot more flexibility? It makes a lot more sense to buy the USB-TTL converter as a module, since at least that is pretty much universal. Or just use a serial connector and have the USB-TTL converter as an external cable for testing/programming if your device doesn't rely on USB being around to actually function.

Comment Re:old clunky junk (Score 1) 170

I don't see anything wrong with a USB HID interface for NES controllers. That's pretty much what AVR-style micros are just right for. Assuming you're using an AVR board with a native USB uC of course, like a Teensy++ or similar. I've done similar things myself, both using custom PIC designs and off the shelf AVR breakout boards. Also, LUFA, which I assume you're using, is great and in general much higher quality code than a lot of Arduino stuff.

If you're using software/bit-banged USB, you really should look into doing it right with a micro that has built-in USB. But that's by no means the worst micro abuse I've seen (and there is actually an argument for doing bit-banged low-speed USB in super low cost scenarios).

Similarly, although I'm not a huge fan of the Raspberry Pi for other unrelated reasons, it's a perfectly fine fit for NES emulation.

Further, another micro for power management isn't too far off either. It's separate enough that I wouldn't want to throw it onto the micro doing HID. I would encourage you to eventually design a more integrated power control board without using a full-blown arduino for it though, and learn to do it using MOSFETs and the like instead of relays, but that's a learning path. I've used my share of relays for quick and dirty power control.

The abuses that I had in mind are nothing like that. It's things like people using an Arduino to run game logic for a video engine implemented in an FPGA (where they could just implement the micro itself in the FPGA and get something much faster than the Arduino without the Arduino), or, on the other end of the spectrum, people using more than one Arduino to do what is effectively blink LEDs (as a one-off/temporary project it's fine, but if you're doing more than one or doing it permanently you really should stop being scared of using bare microcontrollers and learn how to make your own design closer to the requirements - an Arduino is nothing more than a voltage regulator, a USB to serial bridge chip, and a bunch of wires). Or people building entire commercial products around Arduinos with no particular excuse for using them (like compatibility with other projects/modularity), just because they don't know any better and they are too scared to stick a bare chip on a breadboard.

Yes. I'd probably consider 10 or maybe even 20 to be the cut-off for putting more effort into it.

This tells me that you have the right idea, you just need to get over the mental barrier. I deliberately made the threshold low because it really is stupidly easy to use bare chips. An Arduino is nothing more than an AVR with pins broken out, a voltage regulator, and a USB-to-TTL-serial converter onboard. You can get exactly the same effect by sticking an AVR into a breadboard with a 7805, and an external USB to TTL dongle/breakout board. And since for a great many projects you don't need USB, you can keep that external as a debugging aid only. Voila, welcome to the most basic microcontroller circuit: power and ground. You literally don't need anything else (an external clock crystal is helpful for clock accuracy but not required for many applications).

Personally, my threshold is 1. I will use dev boards for microcontroller design prototyping but if I'm ever making more than one, even for myself, I'll roll my own thing. Sometimes I don't even bother prototyping it with a dev board and go straight to a quick and dirty but stripboard build or similar, if it's a one-off but so simple that I know it will work. I mean, why use a clunky Arduino or other dev board when all I really need is an 8-pin chip for a tiny task?

Comment Re:old clunky junk (Score 1) 170

This question is shit. How many more? 50? 500? It doesn't make sense to actually design your own circuit until the number gets up there someplace. Certainly at 5 I would just buy the Arduinos.

I would do my own design at 2. Sometimes at 1.

What you and the people with this problem don't realize is that it's downright trivial to stick the same micro that's on the arduino on a broadboard, give it 5V and ground, and it'll run. You're presumably already designing the rest of the circuit that plugs into the Arduino. Skip the damn thing and just use the chip that it contains directly! The Arduino is a trivial piece of electronics. Count the parts on it. The most complex part of it is the USB to serial converter. You should buy a bunch of those from China (that's what I do, always keep one in my backpack too), design plain TTL-serial ports into your circuits, and just use the converter when you need to talk to the chip (most designs do not need to be in constant communication with a PC to work).

Yeah, all that costs a lot more than just buying some $3 Arduino Nanos from China

No it doesn't. All it takes is to take the pins on your design that say "Arduino goes here" and instead plug in a bare AVR chip. Maybe give it a clock crystal and a voltage regulator. Suddenly, you don't need an Arduino any more. And now you have the freedom to pick a different chip model or family if it fits your design better, if you want. If you insist on treating the Arduino like a magical black box instead, you're not just throwing away money, you're refusing to learn. If curiosity got you interested in making electronics to begin with, why be scared of what's inside the box? The Arduino doesn't even have a case, it's not even hard to see that it really is just very few parts on a board!

Take your work seriously but never take yourself seriously; and do not take what happens either to yourself or your work seriously. -- Booth Tarkington