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Microcontrollers Not Allowed – Trolling a college instructor
- shabble 12y agoReminds me of the excellent EE-trolling magic circuits by Henryk Gasperowicz[1]. The number of things you could bury a little QFN MCU or similar in to play silly buggers with people is huge, especially if you have the luxury of them providing the 'support components'. [1] https://www.youtube.com/user/Fredzislaw100 https://www.youtube.com/user/Fredzislaw100
- letstryagain 12y agoI really want to know how he did this one https://www.youtube.com/watch?v=PC55DPXSpr4 https://www.youtube.com/watch?v=PC55DPXSpr4 I've been watching this video about once a month since 2013 and I still have no idea what's going on!
- jacquesm 12y agoLooks deceive, those are no ordinary LEDs and that's not an ordinary switch. I have a good idea of how this was done but I may be off on the details. The switch contains a coil which is shorted using the switch itself which allows you to detect its presence or absence. That can be used to switch power to an RF oscillator which is connected to another coil, setting up a field over the green paper, relatively close to it. The LEDs contain a flip-flop + some rectification and a cap, each LED can be triggered 'on' or 'off' by completing the circuit between the legs (which otherwise function as antennae, that's why they are bent the way they are, that way they function as a dipole). It's a really neat hack, the guy must have amazing skills if he really has that much hardware tucked away inside the guts of an LED, you'd basically have to hollow out the whole thing, then put an SMD LED at the tip of the housing and use the remainder of the space for the circuitry. Time will tell how much of this was right if and when he reveals how this trick was done.
- usbreply 12y agoI'm on the phone so I won't google, but this is a very old story and if you go to the guy's website, he has a writeup of exactly how he did it. (and yes, the LEDs are hacked, they contain another hidden component)
- jacquesm 12y agoSome googling later: https://plus.google.com/+HenrykGasperowicz/posts/dpwCPFDb3XM?pid=5951325038093105842&oid=116398424278304767741 https://plus.google.com/+HenrykGasperowicz/posts/dpwCPFDb3XM... https://plus.google.com/+HenrykGasperowicz/posts/dpwCPFDb3XM?pid=5933081763604822450&oid=116398424278304767741 https://plus.google.com/+HenrykGasperowicz/posts/dpwCPFDb3XM... https://plus.google.com/photos/+HenrykGasperowicz/albums/5852890237488086849/5945699199587972370?pid=5945699199587972370&oid=116398424278304767741 https://plus.google.com/photos/+HenrykGasperowicz/albums/585... So, indeed. Off on the details though, he's managed to sandwich the whole RF generator into that switch package. Mad props and soldering skills way beyond anything I could ever do.
- TeMPOraL 12y agoYeah, he's good at that. In other video I remember him having hollowed LEDs and putting capacitors inside to create a RC circuit and the 9V battery connector had a microcontroller hacked into it.
- vinceguidry 12y agoMy first guess is that he's passing current over his skin, by touching a power source. The switch has a simple transmitter that turns it on and off.
- jacquesm 12y agoIn the age of 4.5 V 'flat' batteries we did something similar, put an AC generator and another battery inside. (simple sine wave oscillator coupled to a cheap small transformer salvaged from a transistor radio). Watch the local electronics wizz tear their hair out in bafflement how an empty battery (according to the DC volt meter) can power a lamp. Why resort to 4 letter words if you can mess with the laws of physics directly?
- sgt 12y agoI'd love to an electronics related prank in 2015. Just before I went on christmas holiday, I inserted a snippet of JavaScript into our web-based IDE (used by our developers) that flipped images upside down for a few seconds now and then. Their first reactions - this must be a browser issue. Another suspected an issue with the latest OS update.
- sliverstorm 12y agoI never found those quite as fun. "Something is misbehaving, this is annoying!" vs. "This is literally impossible. How is this happening!?"
- simcop2387 12y agoHere's some more modern ones too https://www.youtube.com/watch?v=RkTvDjhImwo https://www.youtube.com/watch?v=RkTvDjhImwo https://www.youtube.com/watch?v=lnlRwPgy3NA https://www.youtube.com/watch?v=lnlRwPgy3NA
- pavel_lishin 12y agoMore magic.
- userbinator 12y agoToo bad the font isn't exactly the same as the real part (look at the 6, 7, and 9 near the end of the video), or maybe that was intentional... One thing that still amazes people today is just how tiny a component can be, and yet provide so much functionality. I've been working with electronics for many years and the feeling still doesn't go away. The die of that microcontroller is even smaller than the package, and if he had access to the right equipment he could encapsulate one and make it basically identical to anyone who didn't look inside: http://www.bunniestudios.com/blog/?p=208 http://www.bunniestudios.com/blog/?p=208 On a more serious note, this brings up thoughts of surveillance implants and backdoors: He could've made that "simulated" display driver record data into the EEPROM of the MCU, and play it back at a later time. An external EEPROM, if the internal one isn't big enough, isn't much bigger; you can get a 256KB EEPROM in a 2x1mm package.
- DanBC 12y agoThe various devices that sit between a computer and a USB keyboard to record the keystrokes are huge compared to how small they could be. http://www.keyghost.com/photos.htm http://www.keyghost.com/photos.htm A well funded TLA could make these really hard to find.
- makomk 12y agoIf I recall the NSA leaks correctly, they already have.
- noonespecial 12y agoI work in a printing plant that has a great deal of tech from the 80's and 90's. Nothing amuses me quite so much as pulling out a damaged obsolete board the size of a pizza box and replacing it with a micro-controller board the size of a playing card and a single screen's worth of code.
- jacquesm 12y agoThe same happens a lot in the industrial control arena. The machines have far outlived their electronics.
- chris_wot 12y agoAt about this point, I feel the urge to explain that basically Tony Abbott (our sledging PM) has basically helped kill off TAFE, but that's ok because his government wants to give students loans at high interest rates for private colleges to give an inferior education. This is the PM whose latest innovation is to setup a ministry for science. Or rather, re setup a ministry for science because he formed the first Australian Federal government in 50 years that had no science ministry. Turns out, that's a bad idea. headslap
- davidgerard 12y agoIt's OK! He put a climate change denier in charge of it ...
- emocakes 12y agogod, you guys are idiots. would you rather vote for a government that is going to crush business and make it harder for you in the future (but hey, its fine! most labor / greens supporters only think of now).
- davidgerard 12y agoOK, I lost it when I got to the image captioned "FUCK."
- sepetoner 12y agoRelatively new EE here with a quick question. You can, technically, make a system with the same output (spelling penis, etc.), without a microcontroller, correct? With the proper frequency dividers, timers, and logic gates? Or am I wrong here?
- kelvin0 12y agoOf course, but then the instructor would have noticed the extra hardware and it would have ruined the fun ...
- TheLoneWolfling 12y agoExpert mode: Make the discrete-component circuit to do this inside the logic gate. (Especially hard as there are components that physically cannot be made small enough (large caps / inductors, etc))
- wiml 12y agoIntermediate mode: You could program the discrete logic onto a tiny CPLD and probably still hide it inside the 74'193. That way you'd still technically be complying with the "no microcontrollers" constraint.
- makomk 12y agoSadly, it's probably a little hard to fit a CPLD in that kind of space without wire-bonding equipment. They also tend to lack the infernal clocks that most microcontrollers have these days.
- snarfy 12y agoI made a BLDC controller using TTL logic. It took about 15 chips. I could have made the same thing with a single 8 pin atiny85.
- shawnz 12y agoYou could reproduce the whole microcontroller with just those things, if you wanted. So inherently the answer is yes. If you mean to ask if it can be done without software, the answer is still yes.
- ChuckMcM 12y agoGenerally if you can pull that off you are way past the course material :-) I had a FORTRAN problem which asked to print the current bowling score given a series of numbers between 0 and 10 (number of pins knocked down) and I had it print out spares as '/' and strikes as 'X' and it didn't print the actual score until you didn't get a strike (as is the custom on bowling.) and the TA complained. (the assignment was to print out the score every frame) but the professor was cool about it and had a nice chuckle so I did get full marks. It is generally a sign of how good the faculty are at an institution based on how they respond to this sort of exceptionalism.
- derekp7 12y agoI had a similar experience with a Visual Basic class at community college (required credit for the degree at the time). Since the class was kind of boring (was already a C programmer, Basic was way in my past at that point), I wanted to make the projects more interesting. So, on a calculator project, we were to make a hand-held calculator emulator. I asked if there were any restrictions on the type of calculator, and was told no -- any one. So I emulated an HP RPN style calculator. But since the instructor never heard of RPN before, and despite an introduction screen explaining it, he still failed the assignment.
- cbhl 12y agoIt baffles me that there are college-level CS instructors who haven't heard of RPN before -- my high school CS teacher had us write an RPN calculator. That said, I can see an argument that an RPN calculator "trivializes" the assignment compared to an infix calculator, especially if the latter was supposed to do order-of-operations.
- derekp7 12y agoThat's the kicker -- order of operations wasn't a requirement (and probably wouldn't have been allowed) either. Maybe I should have put a mode button on it so that you can select the desired mode. But that experience did teach me a valuable lesson -- always follow the specifications as close as possible, don't try to innovate (unless working on your own projects). And, I've learned to spot (and explain) contradictory / intractable specifications up front.
- dripton 12y agoBeautiful. If I were teaching the class, you'd get the A and I'd remember when it was time to write recommendations. But I remember some professors who might have failed a student for pulling something like that. Or even accused him of cheating, for "sneaking in an unapproved piece of rogue equipment." You need to pick your spots.
- bborud 12y agoIdentifying professors that would fail someone for this is actually worth a failing grade. (Though at the age when you are most likely to be a student at a university it probably would seem better to conform and get a good grade)
- obstinate 12y agoWhat aspect of identifying them would make it worth it? I can see some potential fringe benefits -- don't take future classes from that prof, etc. But it's hard to imagine that those fringe benefits would actually be worth the drop in GPA, which does matter.
- MichaelGG 12y agoWhat does GPA matter for? Except special circumstances, like scholarships or visas tied to GPA? I stopped 7th grade and truly dropped out at 10th, so I'm biased. I've just never heard of GPA actually mattering.
- obstinate 12y agoMany companies, including the one I work for, use college GPA as a filter. The theory is: you miss some good folks by filtering out people below 3.5, but you save a lot of effort on a group that has a much higher proportion of bad candidates. If there are enough good candidates above 3.5, this can be a worthwhile trade. Of course, there are ways around this (become famous in the industry, work somewhere else first and do well there, etc.). But most resumes, especially of new grads or people who have only been in the industry for a couple of years, will be run through this filter.
- na85 12y agoAnd now we've learned how an adversary might go about hiding an implant in a personal computer. With more sophisticated fab techniques this would be undetectable.
- gaberowe 12y agoYou probably could have done the project for real in less time than routing out the chip and soldering in the other chip but this is pretty sweet... For all of my EE projects I always did the extra stuff and as a result learned a ton.. The concept that engineering professors have to have stretch goals is really clever to motivate the overachievers.
- derekp7 12y agoIt looks to me like he did do the project for real -- the write up mentions programming the PIC to emulate the other part. Based on that I would guess that you could pull out the hacked chip, and replace it with the 74LS193 and it would work as normal.
- atmosx 12y agoIs there any kit/book/whatever for starters (along with books) to learn this stuff? What goes where, how micro controllers, circuits, etc. work?
- v2vz 12y agoSomething like http://amzn.com/B00005K86O http://amzn.com/B00005K86O will get you started and have a good manual with step by step instructions. They're a lot of fun! (Edit: I know it shows a kid in the picture, but its good adult fun too!)
- pavel_lishin 12y ago> If you attempt this project, your classmates will think you're a nerd. You'll likely wind up getting your head flushed and/or balls greased. I'm familiar with the concept of getting a swirlie (head flushed), but what in the world is getting your balls greased?
- sethammons 12y agoNot sure why you are being down voted. A google search does not answer the question either.
- farkanoid 12y agoUsually done to junior apprentice mechanics in Australia that wear shorts to work (pants are always required in the workshop) They're held down while someone else grabs a wad of black, filthy engine grease. Then they shove said grease up the guys shorts and onto his balls ...It's really hard to get off, man
- pavel_lishin 12y agoThat does sound rather unpleasant :/
- jacalata 12y agoI was more confused by the implication that being a nerd in a Digital Sub-Systems course would somehow make you stand out.
- deleted 12y ago[deleted]
- WillyNourson 12y agoAh remembers me of this "genius" chinese external hard drive scam : http://www.neowin.net/news/fake-chinese-500-gb-external-drive-is-one-clever-paperweight-literally http://www.neowin.net/news/fake-chinese-500-gb-external-driv...
- VLM 12y agoFun anecdote... the 7447 is a BCD to 7seg decoder not a binary/hex to 7seg, so no A thru F output when A thru F are input. There are super expensive options like TIL311 and weird unobtanium that no on has ever heard of. But you can use a PIC in a tight loop checking the 4 inputs, lookup a byte in a 16 byte table, and squirt out 7 bits of LED that display nice A thru F along with the digits. It'll be enormously slower than TTL so you can't build latches that way but works fine for a nice slow asynchronous UI like a LED decoder / driver. This has been redone a zillion times online. Its a good "first microcontroller project". There is at least one ancient 12 or 16 series PIC thats pin compatible with a 7447 with the proper programming although its been 20 years.
- kileywm 12y agoA general comment on how-to instructions: I really respect and appreciate that this article addressed pitfalls where mistakes are common and disastrous. The step involving a router to clear a cavity: lots of mistakes were made, because it's hard to do that step. It takes courage to for an instructor to admit mistakes, and the pupil learns all the better from those admissions. For all of the Instructable, Pinterest, and various other how-to articles on the internet, I believe we could all benefit from instructors being more forthcoming about pitfalls like the author(s) of this article.