While it may not be the case anymore, if you compare a Mac and a PC from 1990, the Mac comes out far ahead. PCs suffered with DOS, while the Mac enjoyed real, non-bitmapped fonts. Where a Windows PC required LANMAN to connect to a network, the Mac had networking built right into every single machine. In fact, any Mac from The Old Days can use this built-in networking to connect to the Internet, but most old Mac networking hacks have relied on PPP or other network to serial conversion. [Pierre] thought there was an incomplete understanding in getting old Macs up on the Internet and decided to connect a Mac Classic to the Internet with Apple’s built-in networking.
Since the very first Macintosh, Apple included a simple networking protocol that allowed users to share hard drives, folders, and printers over a local network. This networking setup was called LocalTalk. It wasn’t meant for internets or very large networks; the connection between computers was basically daisy chained serial cables and later RJ-11 (telephone) cables.
LocalTalk stuck around for a long time, and even now if you need to do anything with a Mac made in the last century, it’s your best bet for file transfer. Because of LocalTalk’s longevity, routers and LocalTalk to Ethernet adapters can be found fairly easily. The only problem is finding a modern device that speaks both TCP/IP and LocalTalk. You can’t use a new Mac for this; LocalTalk has been gone from OS X since Snow Leopard. You can do it with a Raspberry Pi, though.
With a little bit of futzing about with MacTCP and a few other pieces of software from 1993 or thereabouts, [Pierre] can even get his old Mac Classic online. Of course the browsers are all horribly outdated (making the Hackaday retro edition very useful), but [Pierre] was able to load up rotten.com. It takes a while with an 8MHz CPU and 4MB of RAM, but it does get the job done.
Life down on the farm isn’t easy, and a little technology can go a long way to making things easier for the farmer. It’ll be a while before any farmer can kick back on the beach and run his place from a smartphone, but that’s clearly the direction things are heading with this small farm automation project.
[Vince]’s livestock appears to consist of chickens and sheep at this point, and the fact that they share housing helped him to deploy some tech for both species. The chickens got an automated door that lets them out in the morning and shuts them in safely once they’ve returned to roost for the night – important protection against predators. The door is hoisted by a Somfy window-treatment motor, which seems a little on the overkill side to us; a thrift-store electric drill and a homebrew drum might have worked too. A Teensy with an RTC opens and closes the door according to sunrise and sunset times, and temperature and humidity sensors provide feedback on conditions inside the coop. The sheep benefit from a PTZ webcam to keep an eye on their mischief, and the whole thing is controlled by a custom web interface from [Vince]’s smartphone.
There’s just something about automating chicken coop doors that seems to inspire hackers; check out this nice self-locking design. As for [Vince]’s farm, it looks like his system has a lot of room for expansion – food and water status would be a great next step. We’re looking forward to seeing where he goes from here.
If there’s one thing you need in a woodshop, it’s more clamps. There are bar clamps, pipe clamps, spring clamps, and trigger clamps, but for one task in the workshop, no clamp does the job just right. Gluing up panels – a few wide pieces of wood joined on edge – either requires more clamps than you have or cauls, devices that press down on the boards vertically while the clamps press the board together horizontally.
[Andrew Klein] has just invented a new type of clamp for this task, proving once again that not all problems are solved, and there’s still some places where an invention can pop out of mid-air.
The new clamps are a modification to traditional bar clamps that allow for two clamps to interlock. On each of the ‘working’ ends of the clamps, there are two adjustment handles. The first screws the clamp horizontally, just like any bar or pipe clamp. The second adjustment handle moves a bearing up and down. When this bearing meshes with a riser on the mating end of another clamp, the two clamps are pressed together vertically.
The new clamps are effectively clamps and cauls, able to push material together from side to side and top to bottom. The new clamps work, too. In the video below, you can see [Andrew] gluing up a panel. When the vertical adjustment wheel is loosened, the boards come apart vertically. When the vertical adjustment wheel is tightened, the boards are perfectly in line with each other, both edge to edge and face to face.
The 900-pound gorilla in the corner of the Internet of Things (IoT) hype that everyone is trying to ignore is interoperability. In the Internet of Internets (IoI) everything works on a few standards that are widely accepted: IP and HTML. The discrepancies are in the details and the standards wars are in the past. Websites are largely interoperable. Not so in the wild-west ethos of the IoT.
Philips makes a line of ZigBee-enabled RGB lightbulbs that took the enthusiast community by storm. And initially, Philips was very friendly to other devices — it makes a ZigBee-to-WiFi bridge that would let you control all of your ZigBee-based lights, regardless of their manufacturer, from your phone. Until now.
Philips has just rolled out a “Friends of Hue” certification process, and has since pushed out a firmware update where their Hue bridges stop interoperating with non-certified devices. You can read Philips’ version of the story here.
Philips Locks Out 3rd Party ZigBee Hardware
The short version is that, ZigBee standards be damned, your future non-Philips lights won’t be allowed to associate with the Philips bridge. Your GE and Osram bulbs aren’t Friends of Hue. DIY RGB strips in your lighting mix? Not Friends of Hue. In fact, you won’t be surprised to know who the “Friends of Hue” are: other Philips products, and Apple. That’s it. If you were used to running a mixed lighting system, those days are over. If you’re not on the friends list, you are an Enemy of Hue.
Their claim is that third party products may display buggy behavior on a Philips network, and that this loads up their customer-response hotlines and makes people think that Philips is responsible. Of course, they could simply tell people to disable the “other” devices and see how it works, putting the blame where it belongs. Or they could open up a “developer mode” that made it clear that the user was doing something “innovative”. But neither of these strategies prevent consumers from buying other firms’ bulbs, which cost only 30-50% of Philips’ Hue line.
While Philips is very careful to not couch it as such, the Friends of Hue program really looks like an attempt to shut out their competitors; Philips got an early lead in the RGB LED game and has a large share of the market. As they say themselves in their own press release “Today these 3rd party bulbs represent a minimal fraction of the total product connected to our bridges so the percentage of our users affected is minimal.” And they’d like to keep it that way, even though the people they’re hurting are probably their most vocal and dedicated customers.
And while we, with our manual light switches, laugh comfortably at the first-world problems of Hue consumers, we have to ask ourselves whether we’re next. Today they come for our RGB lightbulbs, but tomorrow it might be our networked toasters. A chilling thought!
Snark aside, the IoT brings two of the saddest realities of the software world into your home appliances: Where there’s code, there’s vulnerabilities, and when you can’t control the code yourself you aren’t really in control. You may own the lightbulb, but you’re merely licensing the firmware that runs it. The manufacturer can change the rules of the game, or go out of the product line entirely, and you’re high and dry. What can you do? Pull out your JTAG debugger.
Of course it’s insane to suggest that everyone needs to become an embedded-device firmware hacker just to keep their fridge running. As we’ve written before, we need to come up with some solution that puts a little more control in the hands of the ostensible owners of the devices, while at the same time keeping the baddies out. We suggest a press-to-revert-firmware button, for instance. When Philips pushes a non-consumer-friendly upgrade, you could vote with your fingertips — but then you’d miss out on bug fixes as well. Maybe it’s better to just give in an learn to love Windows 10.
There are no easy solutions and no perfect software. The industry is still young and we’ll see a lot of companies staking out their turf as with any new technology. It seems to us that IoT devices leave consumers with even less choice and control than in the past, because they are driven by firmware that’s supposed to be invisible. It’s just a lightbulb, right?
What do you think? Any ideas about how to put the power back in the hands of the “owner” of the device without everyone’s refrigerators becoming botnet zombies? Let us know in the comments.
“We underestimated the impact this would have upon the small number of our customers who currently use uncertified lights from other brands in the Philips Hue system. We have decided to continue to enable our customers who wish to integrate these uncertified products within their Philips Hue system.”
Light is just a wave, and the wavelength of light determines its color and determines if it can cook food like microwaves, or if it can see through skin like x-rays. There’s another property of waves human’s don’t experience much: polarization, or if the light wave is going up and down, side to side, or anywhere in between.
[David Prutchi]’s project for the Hackaday Prize was like many projects – a simple, novel idea that’s easy and relatively cheap to implement. It’s a polarimetric camera meant to see what humans can’t. By seeing the world in polarized light, the DOLPi can see landmines, cancerous tissue, and air pollution using only a Raspberry Pi and a few Python scripts He gave a talk at this year’s Hackaday SuperConference about polarization cameras and the DOLPi project. After enjoying the video, join us after the break for more details.
“Everything should be made as simple as possible, but not simpler.”
Our journey begins with a fictitious character whom we shall call [John Doe]. He represents the average professional worker who can be found in cities and towns across the world. Most everyday, [John] wakes up to his alarm clock and drives his car to work. He takes an elevator to his office and logs on to his computer. And he does these things without the slightest clue of how any of them work. While he may be interested in learning about the inner workings of the machines and devices he uses on a daily basis, [John] does not have the time and energy to invest in doing so. To him cars, elevators, computers and alarm clocks are completely different and complicated machines with hardly any similarities. It is simply not possible to understand how each of them work without years of study.
The regular readers of Hackaday might see things a bit differently than our [John Doe]. They would know that the electric motor that moves the elevator is very similar to the alternator in his car. They would know that the PLC that controls the electric motor that moves the elevator is very similar to the computer he logs in to. They would know that on a fundamental level, the PLC, alarm clock and computer are all based on relatively simple transistor theory. What is a vast complicated mess to [John Doe] and the average person is nothing but the use of simple mechanical and electrical principles to the hacker. The complication resides in how those principles are applied. Abstracting the fundamental principles from complicated ideas allows us to simplify and understand them in a way that pays homage to Einstein’s off-the-cuff advice, quoted above.
Many of you look at The Calculus the same way [John Doe] looks at machines. You see the same vast, complicated mess that would require a great deal of time and effort to understand. But what if I told you that calculus shares a commonality in much the same way many different machines do. That there are a few basic principles that anyone can understand, and once you do, it will unlock a new way of looking at the world and how it works.
The average calculus course book is a thousand pages long. The [John Does] of the world will see a thousand difficult things to learn. The hacker, however, will see two basic principles and 998 examples of those principles. In this series of articles, I’m going to show you what these two principles – the derivative and the integral – are. Based on work done by Professor [Michael Starbird] of The University of Texas at Austin for The Teaching Company, we’ll use everyday examples that anyone can understand. The Calculus reveals a particular beauty of our world — a beauty that arises when you’re able to view it dynamically as opposed to statically. It is my hope to give you this view.
Before we get started, it pays to understand a little of the history of how The Calculus came about, and how its roots lie in the very careful analysis of change and motion.
Zeno of Elea was a philosopher in the fourth century BC. He posed several subtle but profound paradoxes, two of which would eventually give rise to The Calculus. It would take over 2,000 years for man’s ingenuity to solve the paradoxes. As you can imagine, it wasn’t easy. The difficulties largely revolved around the idea of infinity. How do you deal with infinity from a mathematical perspective? Sir Isaac Newton and Gottfried Leibniz would go on to independently invent The Calculus in the mid 17th century, finally putting the paradoxes to rest. Let us take a close look at them and see what the fuss was all about.
Consider the arrow flying through the air. We can say with reasonable and competent assurance that the arrow is in motion. Now consider the arrow at any given instant in time. The arrow is no longer in motion. It is at rest. But we know the arrow is in motion, how can it be at rest! This is the paradox. It might seem silly, but it’s a very challenging concept to deal with it from a mathematical point of view.
We’ll find out later that what we’re really dealing with is the concept of an instantaneous rate of change, which we will elaborate on with the idea of one of the two principles of calculus – the derivative. It will allow us to calculate the velocity of the arrow at an instant in time – a monumental feat that took over two millennia for mankind to reach.
Let us consider the same arrow again. This time let’s say the arrow is coming at us. Zeno says we don’t have to move, because it can never hit us. Imagine that as the arrow is in flight, it has to cover half the distance between the bow and the target. Once it reaches the half way point, it has to do this again – move half the distance between it and the target. Imagine that we keep doing this. The arrow is constantly moving halfway between its origin and target. By doing this, the arrow can never hit us! In real life, the arrow does eventually hit the target, leaving us with the paradox.
As with the first paradox, we’ll see how to resolve this issue with one of the two principles of calculus – the integral. The integral allows us to deal with the concept of infinity as a mathematical function. It is an extremely powerful tool to scientists and engineers.
The Two Principles of Calculus
The two main ideas of The Calculus will be demonstrated by using them to solve Zeno’s paradoxes.
The Derivative – The derivative is a technique that will allow us to calculate the velocity of the arrow in “The Arrow” paradox. We will do this by looking at positions of the arrow through incrementally smaller amounts of time, such that the precise velocity will be known when the time between measurements is infinitely small.
The Integral – The integral is a technique that will allow us to calculate the position of the arrow in the Dichotomy paradox. We will do this by looking at velocities of the arrow through incrementally smaller amounts of time, such that the precise position will be known when the time between measurements is infinitely small.
It’s not difficult to notice some similarity between the derivative and integral. Both values are calculated by examining the arrow with increasingly finer time intervals. We will learn later that the integral and derivative are in fact two sides of the same ceramic capacitor.
Why Should I Learn Calculus?
We are all familiar with Ohm’s Law, which relates current, voltage and resistance in a simple equation. However, let us consider “Ohm’s Law” for a capacitor. A current flow through a capacitor is dependent on the voltage across it and time. Time is the critical variable here, and must be taken into account in any dynamic event. Calculus lets us understand and measure how things change over time. In the case of a capacitor, the current through it is equal to the capacitance multiplied by volts per second, or: i = C(dv/dt) where:
i = current (instantaneous)
C = Capacitance in Farads
dv = change in voltage
dt = change in time
In this circuit, there is no current flow through the capacitor. The volt meter will read the battery voltage and the ammeter will read zero amps. So long as the potentiometer is not moved, the voltage on the meter will be steady. Our equation would say that i = C(0/dt) = 0 amps. But what happens when we adjust the potentiometer? Our equation says there will be a resulting current flow in the capacitor. This current flow will be dependent on the rate the voltage changes, which is tied to how fast we move the potentiometer.
These graphs show the casual relationships between the voltage across the capacitor, the current through the capacitor and the speed we turn the potentiometer. It starts with the potentiometer turning slowly. An increase in speed results in a faster changing voltage which in turn results in a dramatic increase in current. At all points, the current through the capacitor is proportional to the rate of change of the voltage across it.
Calculus, or more specifically the derivative, gives us the ability to quantify this rate of change, so that we can know the exact value of current running through the capacitor at any given instant in time. The same way we can know the instantaneous velocity of Zeno’s arrow. It is an incredibly powerful tool to have in your hacking arsenal.
In the next article, we will go into deep detail of how we calculate the derivative using a modern but still simple representation of Zeno’s “The Arrow” paradox and some basic algebra. A following article will do the same for the integral using the Dichotomy paradox. Then we will tie things up by showing how the two are related, something known as The Fundamental Theorem of Calculus.
There’s a great game of capture-the-flag that takes place every year at HITCON. This isn’t your childhood neighborhood’s capture-the-flag in the woods with real flags, though. In this game the flags are on secured servers and it’s the other team’s mission to break into the servers in whatever way they can to capture the flag. This year, though, the creators of the game devised a new scoreboard for keeping track of the game: a lightsaber.
In this particular game, each team has a server that they have to defend. At the same time, each team attempts to gain access to the other’s server. This project uses a lightsaber stand that turns the lightsabers into scoreboards for the competition at the 2015 Hacks In Taiwan Conference. It uses a cheap OpenWRT Linux Wi-Fi/Ethernet development board, LinkIt Smart 7688 which communicates with a server. Whenever a point is scored, the lightsaber illuminates and a sound effect is played. The lightsabers themselves are sourced from a Taiwanese lightsabersmith and are impressive pieces of technology on their own. As a bonus the teams will get to take them home with them.
While we doubt that this is more forced product integration advertisement from Disney, it certainly fits in with the theme of the game. Capture-the-flag contests like this are great ways to learn about cyber security and how to defend your own equipment from real-world attacks. There are other games going onall around the world if you’re looking to get in on the action.