Developers Club geek daily blog

Night, street, LED, drugstore

1 year, 12 months ago
It is the third post from series? I will not saw yet, I will not calm down?. (The first? about the laser, the second? about the stun gun)

In 1899 the first manual small lamp (in the kartonovy body), kubsat by DIY kilowatt (equivalent) small lamp, mega-small lamp on LEDs for 3000 rubles (sic has been created!) (provided for cut by green-laser.ru shop).

The Wired log in 2012 in article devoted to the 50 anniversary of creation of LED very strongly has mixed the facts and has incorrectly specified? paternity?. So who father of LEDs?

For now I collected the facts, the childhood and how we did the first engineering attempts was remembered. Usually they occurred after we crowd have watched the movie with Bruce Li (Michael Dudikov or Cynthia Rotrok) in video salon for the Soviet ruble (who for some reason always were in cellars). Having bought the battery? Planet? for 30 kopeks and having unscrewed bulb from parent small lamp, we started assembly. Was to buy small lamp not abruptly, abruptly was to collect the sword of Jedi. And still slope was measured by color of insulating tape.

History of LEDs, assembly instruction of kilowatt lamp and traditional cut

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The motion sensor for switching of radio stations? part II

1 year, 12 months ago
Hi, Habr! Today? continuation of the improvised cycle of detailed posts for beginners. In last post we have taken ready set of the radio designer about Arduino and ultrasonic range finder in order that not only to combine them, and to have opportunity to configure radio? one left?, but also to understand in? Arduinostroyeniya? from scratch. If you have only Arduino and the sensor, you too can try something to collect from this post, but, probably, stop after configure quite good such ultrasonic ruler? that too it is good. I wanted to go further and to put the sensor on the expansion card for creation of the ready device. Here is how it at me left.


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The free textbook of electronics, computer architecture and low-level programming in Russian

1 year, 12 months ago

Misters! I am glad to report that at last everyone can upload the free textbook on more than 1600 pages on which transfer worked more than fifty people from leading universities, institutes and the companies of Russia, Ukraine, the USA and Great Britain. It was really national project and example of the international cooperation.

David Harris and Sara Harris's textbook? Digital circuit engineering and computer architecture?, the second edition, 2012, reduces together the worlds of the software and the equipment, being at the same time introduction and to development of chips, and to low-level programming for junior students. This textbook exceeds earlier input textbook? Computer architecture and design of computer systems? from David Patterson and John Hennessey, and the coauthor of the previous textbook David Patterson himself recommended the textbook from Harrisov as more advanced. Following the new textbook, students build implementation of subset of architecture of MIPS, using payments with COTTON VELVET / FPGA then compare this implementation to industrial Microchip PIC32 microcontrollers. Thus circuit engineering, languages of the description of the Verilog and VHDL equipment, computer architecture, microarchitecture (the organization of the processor pipeline) and programming on the assembler is entered together? generally everything that is between physics and high-level programming.

How to load? Unfortunately, not one click. Snachalo should be registered in the user community of Imagination Technologies, then to be registered in educational programs on the same site then at last to download:

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The panel for photographing with geotags on the basis of LinkIt One

1 year, 12 months ago
The will of destiny of me into hands fell sample of rather interesting payment of LinkIt One from Mediatek. It is the single board computer with impressive set of the periphery prepared for use in the projects connected with wearable devices and IoT.

To receive? the fighting? experience with this controler we have developed the simple panel which is connected to the SLR camera, does pictures and writes shooting point coordinates.

In this article I will tell about the turned-out device and I will share our impressions of work with LinkIt One.


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Training on STM32 in masses

1 year, 12 months ago

Small background


I am the next graduate of certain Moscow higher education institution (I will not specify what, but ordinary). Half a year ago we were told that it is time to write the diploma. At that time I have only just started mastering microcontrollers and it was given me not that it is hard, but with scratch which makes the refrigerator when you, alone, try to shift accurately it, without having damaged precious laminate (in my case linoleum).

My training has begun when I have become interested in subject of microcontrollers and the engineer at whom has taken an interest about them two years ago, has given out me payment 300kh200mm and has told that in it there is STM32F217ZGT6 controler and on this payment there is all necessary for training.? Generally, you will master it? all the rest will seem hogwash? (he, however, has not told that for blinking by LED SPI about which at that time I did not even hear should configure). Later three not really strained month of incorporeal attempts, awareness of weakness of skills of programming and huge number of the read articles it was necessary nevertheless will fork up on STM32VLDISCOVERY and in the way of copying of programs and experiments with them business at last has gone, but all the same slowly.

In one and a half years has managed to work as the developer, looked for vacancies where work with STM32 (as I consider that now is the most perspective microcontrollers of the class), has picked up experience and when business has reached the diploma, has remembered the sore callosities. The idea with subject has come instantly:? Debug payment on STM32 and (full-fledged) training course (for the smallest) to it?.

Yes, I know, I know, from many engineers heard, what with subject? debug payment?? be I the teacher, I would fill up you on protection?, but nevertheless I consider, any idea has the right for life so everything to whom it is interesting, I ask to read further.

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Reverse engineering of flickering LED (+RGB)

1 year, 12 months ago
1.5 a year ago on Habré wrote reverse-inzheniringa of accidentally flickering LED about attempt. Then attempts to analyze patterns of flicker of LED as black box were not crowned with final success? however distribution of skvazhnosty intensity modulation has been set, and the emulator has been written. Lately different groups opened flickering LEDs? and it became known of their work slightly more. At last, hands and at me have reached them.

Lately it was found out, what crystals? accidental blinking?? it is a lot of versions. Photos and reflections of authors on the principle of work of similar crystals? siliconpr0n.org, cpldcpu.wordpress.com, hackaday.com. What not only that someone in detail is engaged in development and mass production such surprises it would seem to insignificant thing as flickering LED? there still is also progress/competition!

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The full guide on robotic designers from Robostation

1 year, 12 months ago


IMHO is not present in the world of the best toy, than the designer. Before emergence of the computer iron beams and plastic cubes were for me out of competition? after all from them it is possible to create the whole world without any restrictions.

Only having matured, I have learned that the meccano is top of evolution of toys on the invention (rather, even opening) which the European teachers have spent hundreds of years, step by step approaching that magnificence that we have now in each children's shop. There are no designers, would not be at me and such thirst for DIY robots.

We at Robostation have ten shops with designers and vsamdelishny roboschool where from these designers collect the real robots. Here also we will talk about it.


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Meteorological station not on Arduino, or Work with timers and interruptions of GPIO in OpenWRT

1 year, 12 months ago
Hi, Habr, did not see long ago!

At first? some important news about the project of microcomputers of Black Swift, and then we will pass to the main subject: as on microcomputer with OpenWRT to make the full-fledged built-in device.

The full-fledged built-in computer, in my opinion, is impossible without two things:
  • Support of interruptions in different occasions, including signals on GPIO inputs
  • Support of hardware timers with the good permission


Without it the considerable part of real problems of automation either is not solved in general, or is solved so that would not decide in general better. The exception is made only by the most banal? to pull the relay, svetodiodiky to pomigat, to trace pair of buttons. Everything, what demands exact timings and/or more or less fast reaction to external events? simply unrealizable without carrying out of the corresponding functionality in the external controler which the above things is able that senselessly complicates construction of the device.

That it is more surprising that at enough microcomputers on SoC Atheros AR9331 and cheaper Ralink RT5350 positioned as the built-in solutions with support in OpenWRT of these two functions everything is extremely sad. Here, of course, there is question to whom these microcomputers at such level of support are necessary? but we will leave it to be groundless.



However, if to look at it on TCP/IP, can descend and for the healthy person.

But at first? news:

  • First batch of Black Swift? in Russia it is also already sent by ruble preorders (that is made not on Kickstarter). If you at the preorder specified delivery? wait, if shipment at own expense? call in office and approach.
  • If you did not make out the preorder, but want to buy Black Swift? call in office and approach, we have very many payments over the volume of preorders. It is possible to issue delivery, but then you for obvious reasons will get up in tail of queue of preorders.
  • Certification of FCC will come to the end soon, apparently? successfully.
  • The satisfaction of beker with Kickstarter, as well as was promised, expected in June. To send to separately Russian-speaking or any else separate beker of payment we cannot on technical features of Kickstarter.
  • Slowly documentation, because of lack of time is replenished? first of all the English-speaking.
  • In particular, images of virtual computers with OpenWRT SDK and Eclipse? here (in couple of days I will update them on the fresh SDK version with our patches). Are useful to all who wants to write something under OpenWRT, but not really understands, how.


And now? to subject.

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DDA for cat

1 year, 12 months ago
There is at us in family cat by the name of the Pussycat. Young, and also cowardly and curious at the same time. The only thing, what absolutely fights off it all cowardice? this red laser speck from boshevsky range finder. She is ready to hunt for it recklessly. But. The range finder has time limit on work, batteries on it will not save enough and vly on long games with cat to waste time.

Found any automatic cat's teasers on Internet open spaces? expensively and the functionality is limited. Besides, there is no guarantee that the ray will not get on curtains, and they will not be thus subwounds completely.



Or we are not engineers-electronics engineers-arduinshchiki?! And most to collect?

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That means the robot to develop

1 year, 12 months ago
You read about robots and programming and think:? It would be healthy to make something similar most!? Those whom this idea seizes slightly more simply than thoughts look who and as did the robot. Read articles, watch video. On pictures all is clear. In videos too already ready-made products usually are shown, and also is compressed technologies of their production are shown. And, it seems, the same everything is clear: has sawn off, has fastened, has soldered, has connected, has programmed on that program this code.

Even more keen, having selected interesting and, at first sight, simple option, pass to action and, often copying, do the first robot. This strong-willed and very significant solution? to begin though something to make the main thing most! In the course of production there is heap of technology tricks up to that it appears for order/purchase of some shtukention, it is necessary to learn as it precisely is called. And still? connectors are not soldered normally? and how on video in one contact everything turns out? Process of creation is quite often dragged out, but the persistent beginner of robotics anyway finishes result before some intelligent first start at least? on straight line?.



Then, when the robot is finished, the understanding why everything becomes quite so and exactly in such sequence comes. Process of creation can already be realized, formalized, painted somehow. Here from this point development of model of the following, second generation also begins.

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