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Microcontrollers Not Allowed – Trolling a college instructor

ultrakeet.com.au

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Re: Microcontrollers Not Allowed – Trolling a college instructor

#32
post #29
post #13

Earlier quoted context omitted.

I 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…

It 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.

That'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.

Re: Microcontrollers Not Allowed – Trolling a college instructor

#33

Relatively 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?

Definitely. You could make a small hardwired state machine and decode its various states into the behavior you wanted, for example. It would probably take a dozen or so 7400-series logic chips (depending on how complex the easter-egg behavior is).

That kind of small, non-microprogrammed machine is really common, but people don't build them out of discrete logic any more, or probably even design them by hand. They're written in VHDL or something, and synthesized into silicon or a gate array. They're how a programmable controller is implemented (something has to be under the bottom-most layer of microcode), but they're also used for lots of other little peripheral tasks.

I'd guess the student in the article will be formally taught about them in another quarter or two.

Re: Microcontrollers Not Allowed – Trolling a college instructor

#34

You 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.

It 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.

Re: Microcontrollers Not Allowed – Trolling a college instructor

#35
post #9

Earlier quoted context omitted.

Of course, but then the instructor would have noticed the extra hardware and it would have ruined the fun ...

Expert 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))

Intermediate 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.

Re: Microcontrollers Not Allowed – Trolling a college instructor

#36

Earlier quoted context omitted.

What 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.

http://en.wikipedia.org/wiki/Dunning–Kruger_effect

Michael Dell, Bill Gates

Re: Microcontrollers Not Allowed – Trolling a college instructor

#37
post #2

Reminds 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

I really want to know how he did this one

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!

Re: Microcontrollers Not Allowed – Trolling a college instructor

#38
post #31

Is there any kit/book/whatever for starters (along with books) to learn this stuff? What goes where, how micro controllers, circuits, etc. work?

Something like 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!)

Re: Microcontrollers Not Allowed – Trolling a college instructor

#39
post #36

Earlier quoted context omitted.

http://en.wikipedia.org/wiki/Dunning–Kruger_effect

Michael Dell, Bill Gates

Gates knew his family was rich enough that he could go back and finish his degree if the business didn't pan out. If you've got that financial cushion and you've got something better to do with your time then sure, drop out. But dropping the GPA "just because" is probably not your best option.

Re: Microcontrollers Not Allowed – Trolling a college instructor

#40

Earlier quoted context omitted.

Not caring about your GPA sounds like a great way to filter out companies that use bogus criteria as a way to filter prospective employees.

That's an option, but you're going to end up filtering out a lot of the best companies to work for if you go that route. I have personal knowledge that it's a factor at least at Google and Microsoft. As I understand it, Facebook and Twitter use it as well. All depends on what you value. Personally, it seems like getting a high GPA isn't very difficult, so why not do well in school to keep your opportunities as open a…

YMMV but those are all terrible companies to work for.

Consider this they collectively employ ~ 100,000 people and have produced basically zero innovation in the last 3 years.

PS: Though they also have fairly wide side doors so many of their current employes have not gone thorough their screening process.

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