Feed aggregator

Hacking A Very Special 486

Hackaday - 6 hours 30 minก่อน

It’s fair to say that Moore’s Law is not delivering on its promise of advancing semiconductor capabilities as fast as it used to, as the limits of current fabrication techniques are being met. Where this is being written for example there are two laptops, one from the last year and one that is 11 years old, and while the new one is undeniably faster it has not overtaken the other by as much as a ten year gap between 1990s machines would have revealed.

So with older laptops being still so relatively quick, what possible attraction could there be for working on a machine from the 1990s, when the Moore’s Law curve was steeper? It’s something [Jim W] is doing, with his HP Internet Advisor (J2522B), and when you see the machine in question perhaps you’ll understand why. The J2522B is a laptop, but it’s no ordinary ’90s road warrior’s status symbol. This 486-powered beast is a piece of test equipment, specifically one for examining Ethernet ports, thus it’s built like a tank and is mains powered only. It boasts a 486DX4, 16 MB of memory, a then-colossal 1.3 GB hard drive, and an ISA Fast Ethernet card. Oh, and WIndows 95, which with a couple of decades’ hindsight seems an amusing choice to power a piece of security test equipment.  Impressive specs for the day, but the $20,000 price tag would still have been steep compared to a comparable laptop.

[Jim]’s machine is destined for classic gaming, though with only the little HP pop-out mouse you saw on their Omnibook range at the time, he needed a PS/2 port. Some chipset hunting found that, but at the cost of accidentally frying a MOSFET when a screen connector was incorrectly re-inserted. We’re then treated to a guide to substituting older MOSFETs with modern parts, useful in itself, but followed by a marvelous piece of bodge work as an SOIC-8 part is placed on a DPAK footprint.

This is an interesting series of posts, partly from a retro angle as they deal with an interesting machine, but also from a hacking angle as he’s getting closer to the vintage PC hardware than most of us to. Keep an eye on it, there is sure to be more in the pipeline.

HOPE XIII: Oh The Fun You’ll Have With a Bit of Social Engineering

Hackaday - เสาร์, 07/21/2018 - 21:00

I’ve been aware of the Social Engineering panels, talks, and villages at many conferences over the past few years. For some reason, be it the line to get in or conflicting schedules, I haven’t made it to one. Today was my day and I had a blast. The Social Engineering Panel at HOPE XIII is a great introduction to the dark(ish) art and a stroll through memory lane with some notables in the field.

Social Engineering (SE) is the pseudo-science of getting what you want by convincing people to share information, usually without them even knowing they’re doing so. This particular panel focused on over-the-phone SE and the four panel members began with a simple illustration. SE has changed over the years in large part because it is increasingly difficult to get a human on the phone. For about ten minutes an attempt was made to reach a person at Verizon, AT&T, and Spectrum Cable. With a two minute limit per phone number, all were fails.

But this didn’t derail the talk, which featured story time from Emmanuel GoldsteinAlexander J. Urbelis, Flyko, and Cheshire Catalyst. As phreakers back in the day, and tele-social engineers still, the stories were very entertaining. The panel was live streamed but doesn’t look like the video is available on demand yet so I’ll give you a quick and entertaining overview.

Story Time

Alexander’s story begins with the age-old practice of auto-dialing every 800 number and looking for automated systems that pick up. In the mid-90’s this would net you the front door of the new technology of voicemail. Mailboxes with weak pin numbers were taken over by phreakers who use them as a toll-free voice BBS. When the company caught on they reported it to AT&T corporate security who began logging the activity. If they identified you as a phreaker, they would disconnect the ability of your extension to use the 800 number service and send a nasty letter in the mail asking you to call. Alex realized that the number you were calling was actually an answering machine and tried the remote access code that worked for his home answering machine at the time: the number 10. It worked and he was able to listen to the recordings of all the other phreakers who got busted. He turned around and called those freaked out phreakers, pretending to be AT&T security! After giving them a hard time he fessed up and told them the trick so they could have some fun too.

Emmanuel also found voicemail systems but in the 1980’s, but his run-in was with the FBI and not merely telephone network security. He got onto the IBM voice service called Telemail by dialing 1-800-426-2222. The system used a computer voice which asked you to keypress your last name. He managed to get an access code using “Gary Smith”. Unfortunately, the FBI was monitoring. But through an interesting bit of luck, the phreakers were able to get voicemail box access of the person giving the Bureau information. Emmanuel called up the field agent and spoke with him for 45 minutes posing as the informant, resulting in a derailing of the case in progress. The piper did eventually come calling and Emmanuel spent some time helping advise on how to better secure the system. He said the FBI had egg on their face but were pretty cool about it: “They realized we weren’t bad people, we just didn’t want to go to prison for using voicemail”.

Social Engineering: the Life Skill

It’s interesting to hear advice from these panelists on how to responsibly use SE skills.

Flyko closed with the message that for day-to-day life, listening skills and empathy are really important and they happen to be the most powerful parts of SE. You don’t need to be aggressive, that turns people off. Trigging their empathy gets people wanting to help you, and you get a lot more out of that. His approach is one that gathers people into his corner: “my system’s been slow all morning, I’m trying to figure this out…”.

The point was also made that the seed for success can be very small. Just two little pieces of information can get you a long way if people assume that only insiders could have that kind of information. Use that and put on the right persona. You can be anyone you want at the other end of that phone line. Free yourself to take advantage of that.

Emmanuel’s closing is a good mantra if you want to explore this realm: “It’s good to have fun. It’s not good to be irresponsible and put lives at risk”

We’ll keep our eyes out for the video of this talk to go live and remind you. This is one you just have to see!

Measuring Web Latency in the Browser

Hackaday - เสาร์, 07/21/2018 - 18:00

We’ll go out on a limb and assume that anyone reading these words is probably familiar with the classic ping command. Depending on which operating system you worship the options might be slightly different, but every variation of this simple tool does the same thing: send an ICMP echo request and wait for a response. How long it takes to get a response from the target, if it gets one at all, is shown to the user. This if often the very first step to diagnosing network connectivity issues; if this doesn’t work, there’s an excellent chance the line is dead.

But in the modern web-centric view of networking, ping might not give us the whole picture. But nature it doesn’t take into account things like DNS lookups, and it certainly doesn’t help you determine what (if any) services the target has available to you. Accordingly, [Liu Zhiyong] has come up with a tool he calls “pingms”, which allows you to check web server latency right from your browser.

Rather than relying on ICMP, pingms performs a more realistic test. It takes the list of targets from the file “targets.js” and connects to each one over HTTP. How does it work? The code [Liu] has come up with will take each target domain name, append a random number to create a gibberish filename, and then calculate how long it takes to get a response when trying to download the file. Obviously it’s going to be getting a 404 response from the web server, but the important thing is simply that it gets the response.

With this data, [Liu] has come up with a simplistic but very slick interface which shows the user the collected data with easy to understand color-coded graphs. As interesting as it is to see how long it takes your favorite web sites or service providers to wake up and start talking, watching the colored bars hop up and down the list to sort themselves is easily our favorite part of pingms.

[Liu] has released pingms under the GPLv3 license, so if you’re looking to utilize the software for your own purposes you just need to provide a list of test targets. If you need to perform low-level diagnostics, check out this handy network tester you can build for cheap.

Digital Attenuator Goes from Manual to Arduino Control

Hackaday - เสาร์, 07/21/2018 - 15:00

[Kerry Wong] comes across the coolest hardware, and always manages to do something interesting with it. His widget du jour is an old demo board for a digital RF attenuator chip, which can pad a signal in discrete steps according to the settings of some DIP switches. [Kerry]’s goal: forget the finger switch-flipping and bring the attenuator under Arduino control.

As usual with his videos, [Kerry] gives us a great rundown on the theory behind the hardware he’s working with. The chip in question is an interesting beast, an HMC624LP4E from Hittite, a company that was rolled into Analog Devices in 2014. The now-obsolete device is a monolithic microwave integrated circuit (MMIC) built on a gallium arsenide substrate rather than silicon, and attenuates DC to 6-GHz signals in 64 steps down to -31.5 dBm. After a functional check of the board using the DIP switches, he whipped up a quick Arduino project to control the chip with its built-in serial interface. It’s just a prototype for now, but spinning the encoder is a lot handier than flipping switches, and once this is boxed up it’ll make a great addition to [Kerry]’s RF bench.

If this video puts you in an RF state of mind, check out some of [Kerry]’s other videos, like this one about temperature-compensated crystal oscillators, or the mysteries of microwave electronics.

Open Source Laboratory Rocker is Super Smooth

Hackaday - เสาร์, 07/21/2018 - 12:00

Lab equipment is often expensive, but budgets can be tight and not always up to getting small labs or researchers what they need. That’s why [akshay_d21] designed an Open Source Lab Rocker with a modular tray that uses commonly available hardware and 3D printed parts. The device generates precisely controlled, smooth motion to perform automated mild to moderately aggressive mixing of samples by tilting the attached tray in a see-saw motion. It can accommodate either a beaker or test tubes, but since the tray is modular, different trays can be designed to fit specific needs.

Source code and schematics are available from [akshay_d21]’s Google Drive and the 3D models are also available from the National Institute of Health’s 3D Print Exchange. A demonstration video is embedded below, in which you can see how smooth and controlled the motions are.

DIY lab equipment really benefits from the recent growth in desktop manufacturing and part availability; this one is in good company along with the DIY Laboratory Dry Bath and this DIY Syringe Pump.

Bananas Against Racism

Hackaday - เสาร์, 07/21/2018 - 09:00

This is a tale as old as time. Not love, it is about keeping something you made safe from those who would destroy something beautiful. In this case, the thing of beauty is a talking banana who reads Twitch and Youtube comments. The ne’er-do-wells are trolls seeking to ban-anana the account by forcing it to recite restricted words.

The problems stem from a visit from [Greekgodx], whose followers tend toward the dark side. When they set their sights on [Mike Nichols]’ yellow automaton, things slipped into a bleak place, and a twenty-four-hour ban falls on the fruit. A bunch of filtering is done, but it isn’t enough to stop the trolls, and the tally-man adds a second permanent strike against the account. An arms race of slurs and filtering ensued until the robot was able to reject all attempts at racism.

The banana has since been peeled from the feeds, but if silly robots are your cup of tea, check out [Simone Giertz] turning a car into a computer mouse.

Thank you [Itay] for another fruitful tip.

Twin ‘T’ CW (Morse) Practice Oscillator

dangerous prototype - เสาร์, 07/21/2018 - 06:55

 

Steve Smith (G0TDJ) writes, “I successfully completed the Twin ‘T’ Oscillator, original by Mike Maynard – K4ICY. It’s a great circuit and sounds really good. Much better than a raspy 555 version. Mike has been kind enough to put a link to my project on his website.”

More details at www.ProjectAVR.com.

Failed 3D Print Saved with Manual Coding

Hackaday - เสาร์, 07/21/2018 - 06:00

Toast falls face down. Your car always breaks after the warranty period. A 3D print only fails after it is has been printing for 12 hours. Those things might not always be true, but they are true often enough. Another pessimistic adage is “no good deed goes unpunished.” [Shippey123] did a good deed. He agreed to make a 3D printed mask for his friend to give as a gift. It was his first print he attempted for someone else after about four months’ experience printing at all. After 20 hours of printing, he noticed the head was moving around in the air doing nothing — a feeling most of us are all too familiar with. But he decided not to give up, but to recover the print.

Luckily, he’s a CNC machinist and is perfectly capable of reading G-code. The first thing he did was to shut everything down and clear the head. Then he rehomed the printer and used the head to determine what layer the printer had been working on when it failed. He did that by moving over a hidden part of the print and lowering the head by 100 microns. Then he’d move the head a few millimeters in the X direction to see if the head was touching.

Turns out the printer was probably on the 40mm layer when it froze, but to play it safe, he decided to resume printing at 33.8mm. For this kind of print, being off by 200 microns would hardly be noticeable.

In general, G-code produced by a slicer has a preamble that sets certain parameters like temperatures and speeds. Then it has a bunch of move codes like G1 and G0. Typically, there will only be one G0 line per layer that has a Z parameter. This is the line that changes the layer.

In this case, it was layer 168 that had the line:

G0 X143.779 Y205.684 Z33.8.

The only thing he had to do was delete from the top up to and including that line. Then he had to script a little preamble that would set everything up without crashing into the existing print. Essentially he did the normal startup script but moved the head higher than the print from the home position. Then he moved to the correct spot and lowered the head to 33.8 mm before resuming the script:

G0 F3000 Z35.8 G0 X143.779 Y205.684 G0 Z33.8

The thin layer height probably helped. If you were doing very thick layers, you could easily have part of the makeup layer droop. Then again, it might be worth a try.

As you might expect, though, the process did leave a little line around that layer. After the print completed, he used a hobby knife to trim the line and then sanded with fine sandpaper. The end result looks pretty good.

If you are too lazy to do all this work yourself, you can automate it. Of course, sometimes you need to save your 3D prints from yourself.

Free PCB coupon via Facebook to 2 random commenters

dangerous prototype - เสาร์, 07/21/2018 - 05:25

Every Friday we give away some extra PCBs via Facebook. This post was announced on Facebook, and on Monday we’ll send coupon codes to two random commenters. The coupon code usually go to Facebook ‘Other’ Messages Folder . More PCBs via Twitter on Tuesday and the blog every Sunday. Don’t forget there’s free PCBs three times every week:

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • We’ll contact you via Facebook with a coupon code for the PCB drawer.
  • Limit one PCB per address per month, please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

Arduino Powered Arcade Button Lighting Effects

Hackaday - เสาร์, 07/21/2018 - 03:00

As if you already weren’t agonizing over whether or not you should build your own arcade cabinet, add this one to the list of compelling reasons why you should dedicate an unreasonable amount of physical space to playing games you’ve probably already got emulated on your phone. [Rodrigo] writes in to show off his project to add some flair to the lighted buttons on his arcade controller. (Google Translate)

The wiring for this project is about as easy as you’d expect: the buttons connect to the digital inputs on the Arduino, and the LEDs on the digital outputs. When the Arduino code sees the button getting pressed, it brings the corresponding LED pin high and starts a fade out timer using the SoftPWM library by [Brett Hagman].

It’s worth noting that the actual USB interface is being done with a stand-alone controller, so the Arduino here is being used purely to drive the lighting effects. The more critical reader might argue that you could do both with a single microcontroller, but [Rodrigo] was in a classic “Use what you’ve got” situation, and already had a USB controller on hand.

Of course, fancy lit arcade buttons won’t do you much good without something to put them in. Luckily we’ve covered some fantastic looking arcade cabinets to get you inspired.

Bucky Glow: Have a Ball While You Practice Coding

Hackaday - เสาร์, 07/21/2018 - 01:30

About a year ago, [Jonathan Bumstead] built a giant, touch-sensitive, interactive RGB LED geodesic dome that somehow escaped our attention entirely. For this year’s Hackaday Prize, he’s designed a smaller version that’s just as awesome, but a lot faster and easier to build.

The Bucky Glow is great way for hackers of all ages to expand their coding and problem solving skills. This interactive dodecahedron consists of 11 RGB LEDs and a Nano inside 12-sided laser-cut MDF sculpture. The breakout header means you’re free to add interactive bits like a DIY capacitive touch keyboard, IR sensor/emitter pairs, motors, or whatever you want.

When it’s time to relax, Bucky Glow puts on a light show. It comes ready to party without any programming necessary, but if you wanna put on some Pink Floyd and get your hands dirty, [Jonathan]’s custom Processing app makes it easy to program complex light shows.

[Jonathan] is currently working on some different Bucky Glow dissemination methods, such as a kit version. For now, you can buy a fully assembled Bucky Glow through the One Bit Kit store. Interact with the break to try it before you buy it.

The HackadayPrize2018 is Sponsored by:





GPD Pocket 2 handheld PC launch imminent (already up for pre-order in China)

Liliputing - เสาร์, 07/21/2018 - 00:16

The upcoming GPD Pocket 2 is a handheld computer with a 7 inch full HD display, a QWERTY keyboard, and a laptop-style design. As the name suggests, it’s a second-generation device and the new model has a faster processor, a redesigned keyboard, and some other improvements. GPD plans to launch a crowdfunding campaign for the […]

The post GPD Pocket 2 handheld PC launch imminent (already up for pre-order in China) appeared first on Liliputing.

Belgrade Badge Hacks

Hackaday - เสาร์, 07/21/2018 - 00:01

We’re still coming off the Hackaday Belgrade conference right now. If you were there, you know it was the greatest hardware conference ever. If you weren’t there, you missed out. Sorry. (Make sure you get in on the Hackaday Superconference in November.)

One of the many highlights of the Belgrade conference was, of course, the badge. The 2018 Hackaday Belgrade Badge is a masterpiece of hardware with a 55-key keyboard, RGB TFT LED, speaker, and a BASIC interpreter.

This badge is a masterpiece of electronic design by Voja Antonic. Just to take one small example from the design, check out the placement of the buttons. Think the slightly rotated buttons that make up the keyboard is only a stylistic choice? It’s not; by carefully rotating each button, the legs of each switch can fit in between each other. It’s brilliant.

Starting hardware this good, adding amazing software by Jaromir Sukuba to bring it to life, and distributing a badge to each hacker through the door is the perfect recipe for some amazing hacks. What were the best badge hacking tricks we saw at the 2018 Hackaday Belgrade conference? Check out the video of the badge hacking ceremonies and then join us below for a few of our favorites.

I made a demo for the Hackaday Belgrade badge. The timeframe for coding the thing was limited and showcasing it als… twitter.com/i/web/status/1…


kory.io (@KoryNico) May 28, 2018 Demoscene!

After decades, the demoscene has been elevated to an art. This is the community built around pushing pixels, blitting blitters, and generally squeezing every last bit of performance out of a computer system, for the sole purpose of making really cool graphics and awesome music.

The Hackaday Belgrade badge has an enormous display with full color, so it only makes sense there would be a few demoscene entries to our badge hacking competition. One of the best comes from [kory.io], who made a demo featuring high-resolution images and real-time rendered plasma effects along with pre-rendered animation.

Of course, this requires a video, so dig into this spectacular demo posted to Kory’s Twitter feed.

A Modem!

[bosko]’s ‘modem’ for the Belgrade BadgeThe 2018 Belgrade Badge is designed to be a wearable version of a home computer. With the inclusion of an expansion header, it’s begging to have more hardware connected. The badge has a full BASIC interpreter, and the TX and RX lines of a serial port are just sitting there. What could this possibly mean?

For [bosko], home computers meant connecting to the world through BBSes. Is that even possible with this badge? Of course it is, all you need is a modem.

Since acoustic couplers don’t fit smartphones, [bosko]’s ‘modem’ is actually a NodeMCU board with an ESP8266. Yes, it’s a WiFi to serial port adapter, pieced together out of three dollars worth of hardware and a few jumper leads. The code running on the badge is extremely simple, and basically just pushes bytes to the serial port. For the modem, [bosko] is just using the AT command set found in every ESP.

[bosko] did manage to connect his modem to a network, and even managed to pull up a BBS on the badge. It’s slow, yes, but really, what did you expect.

It’s a great proof of concept, and given that WiFi to serial adapters literally only cost two dollars, we can’t wait to see what else this badge can do. Is it possible to write a browser? We have just the website for that, and another one of the hacks shown during the badge hacking ceremony did manage to load up our retro page!

Shoot My Valentine

When you think of multiplayer games, Fortnite is probably the first thing that comes to mind. Actually, it’s probably not, but throwing the word ‘Fortnite’ into any post really helps out with SEO. Multiplayer games have been around for decades, but in the olden days they were a pain to configure. Does anyone remember IPX? Yeah, exactly.

With a home computer on a badge and a convenient serial port, it’s entirely possible to write a multiplayer game using a null modem cable made out of Dupont connectors. That’s exactly what [kramarb] did with his badge hack, Shoot My Valentine and the results are way more fun that might first think.

The game is extremely simple — it’s just a spaceship from Space Invaders shooting pixels up the screen. Two badges can play this game, and each badge tries to kill the other player by sending bullets over the serial port.

This is brilliant. It’s a real multiplayer game played over a serial port, all coded in just a few hours at the Hackaday Belgrade conference. Going further, it wouldn’t be too hard to make this game run wirelessly, possibly using a few IR LEDs. It would be amazing, and probably almost as reliable as the multiplayer on those old DOS games.

This Isn’t the End of our Retrocomputer Badge

The 2018 Hackaday Belgrade badge was a smashing success, and the best example yet we’ve had for what can be done with electronic conference badges. We’re planning a gigantic conference this November, the fourth annual Hackaday Superconference. The badge for the Supercon? All we can say now is that it will be based heavily on the best of the Belgrade badge. First, though, we need to buy the entire world’s supply of one particular brand of tact switches — there were over 20,000 of them in the room at Belgrade!

What does this mean? It means more opportunities to hack this badge. It might just be possible to add a floppy drive to this badge, and we want to see you try. We know it’s possible to get this badge on the Internet, and we want to see where people can take that. The entire purpose of this badge is to do something really fun with it during the three days of the con, and we can’t wait to see the other astonishing badge hacks that will be developed around this platform.

Hackaday Passes 100,000 Subscribers on YouTube

Hackaday - ศุกร์, 07/20/2018 - 23:01

Check it out, the Hackaday YouTube channel just passed 100,000 Subscribers! Thank you to everyone who has been following the great stream of videos on our channel. If you’re not yet following us, now’s the time!

We’ve upped our video content game over the last couple of years and the steady stream of awesome is the reason so many people are subscribing. With this milestone reached, it’s a great time to look at the different styles of content Hackaday focuses on, and to get some feedback about what you would like to see on our channel!

Anyone following along with the Hackaday Prize looks forward to regular updates from Majenta Strongheart. Her most recent installment covers robotics, and her power harvesting overview will hit the channel in about a week. Behind that camera and in the editing booth Jordon Clark really makes these updates look spectacular. Jordon has also been working on a lot of other content. He launched a series of the project features from Hackaday.io and makes the live streams from Hackaday meetups look and sound great! Here’s Christine Sunu’s Emotive Robotics talk from the Hackaday LA meetup in May.

Of course we continue to do videos on new product features and releases (the Arduino Vidor reveal at Maker Faire was a big hit), as well as tutorial videos like the latest guide on pad printing which Brian Benchoff published this week. This is also the channel where you’ll find all of our Hackaday conference coverage, from livestreams, to on-site interviews and the recordings of all the talks — here’s Rachel Wong’s keynote from Hackaday Belgrade.

Thank you to everyone who has been watching, and to all of the Hackaday crew who put incredible passion into producing fun, high quality videos. We’re always looking for ideas so please let us know in the comments, what would you like to see on Hackaday’s YouTube channel?

Updates by Majenta Strongheart Meetup Talk Livestreams Scotty Allen Interview

Build A Boat With Your Buddies

Hackaday - ศุกร์, 07/20/2018 - 22:00

It’s probably a dream common to many groups of friends among the Hackaday readership: go away together to a sunny island some time in the summer, take a load of beer and maybe a BBQ, and build something. Some of us get close to it at hacker camps such as Toorcamp or EMF, but few do it as well as [KristianKalm] and his friends. Their time on an island resulted in a boat, and what a boat it is!

To be fair, this is not a craft you’d sail the high seas in, its unique hull design rendered in single-skin plywood might have some stability issues and probably would have difficulty maintaining structural integrity in a high sea. But it’s perfect for their summer time backwater, with its electric outboard, steering wheel, and seat from a Russian saloon car.

The plans are fairly simple, cut from two sheets of ply it has an angular pointed front, sloping sides, and a fairly narrow bottom. Our experience with river boats would have led to a wider flat-bottomed hull, but this one looks stable enough for their purposes. Everything is held together with PVA glue and extra pieces of wood over the joints, something that amazingly keeps the water at bay. It is fairly obviously a rather basic and ever some might say rather ugly boat, but we’d guess there are few readers who wouldn’t want to give it a spin as part of a summer holiday.

If this has caught your fancy, don’t panic, the Northern Hemisphere still has some summer left, and all you need to do is find a plastic barrel!

Thanks [Keith Olson] for the tip!

Daily Deals (7-20-2018)

Liliputing - ศุกร์, 07/20/2018 - 21:30

Didn’t get a chance to snag a Instant Pot 7-in-1 cooker for $59 on Amazon Prime Day? Apparently the uber-popular kitchen companion was one of Amazon’s most popular items, although I didn’t mention it in our roundup because, well, it’s not the sort of tech we usually cover. That said, several friends told me I should […]

The post Daily Deals (7-20-2018) appeared first on Liliputing.

Learn to Count in Seximal, a Position Above the Rest

Hackaday - ศุกร์, 07/20/2018 - 21:01

Believe it or not, counting is not special. Quite a few animals have figured it out over the years. Tiny honeybees compare what is less and what is more, and their brains are smaller than a pinky nail. They even understand the concept of zero, which — as anyone who has had to teach a toddler knows — is rather difficult to grasp. No, counting is not special, but how we count is.

I don’t mean to toot our own horn, but humans are remarkable for having created numerous numeral systems, each specialized in their own ways. Ask almost anyone and they will at least have heard of binary. Hackaday readers are deeper into counting systems and most of us have used binary, octal, and hexadecimal, often in conjunction, but those are just the perfectly standard positional systems.

If you want to start getting weird, there’s balanced ternary and negabinary, and we still haven’t even left the positional systems. There’s a whole host of systems out there, each with their own strengths and weaknesses. I happen to think seximal is the best. To see why, we have to explore the different creations that arose throughout the ages. As long as we’ve had sheep, humans have been trying to count them, and the systems that resulted have been quite creative, if inefficient.

The Simple Grouping System Symbol I V X L C D M Value 1 5 10 50 100 500 1,000

Way back when, somebody decided that tally marks just weren’t cutting it. From that frustration, the simple grouping system was born[1].

By definition, it’s simple. Pick any integer you like; call it b. Now, decide upon a symbol for the powers of b: 1, b, b², and so on. Then any integer can be represented as a grouping of those symbols, simply adding them together. If you have a number that’s equal to 1 + 1 + 1 + b + b + b + b² and want to write it down, all that’s necessary is to drop the plus signs and smush the symbols together (111bbbb²), making addition of any two numbers in your system extremely intuitive. You could even rearrange them if you liked. b²bbb111 represents the same number as you have to add them all together anyway.

A familiar — if somewhat irregular — example of such a system appears in the Roman numerals, which takes b to be 10. If you want something a bit more regular, the ancient Egyptian numerals shown below, also taking b to be 10, fit the bill quite nicely.

Symbol

Hate smartphone notches? How about a hole in the display?

Liliputing - ศุกร์, 07/20/2018 - 20:21

In an attempt to give phones a higher screen-to-body ratio, most major smartphone companies have settled on a solution: phones with taller screens and slimmer bezels… often with a display that wraps around a camera cut-out, or notch. A few companies, including Vivo and Oppo have figured out how nearly eliminate the top bezel without […]

The post Hate smartphone notches? How about a hole in the display? appeared first on Liliputing.

PCBWay after-sale service review

MCU Project everyday - ศุกร์, 07/20/2018 - 19:28

When I need PCB prototype and PCB assembly service, the first manufacturer jumps to my mind is PCBWay. Because of their good PCB quality and excellent service, you can get quick response for any questions.

Recently I am planning to participate in makerfaire that held in my city. I plan to show my arduino project and offer small gifts to the audience who likes my project. I chose PCBWay ruler as a gift that found in PCBWay open source community, it seems very good.

After 7 days I received the PCBWay ruler, here is the picture:

 

This ruler looks beautiful, right? Good silkscreen, matt black solder mask, immersion gold, but did you find out anything wrong?

Yes, the series of holes, only the first three holes were immersion gold. I don’t know why this problem happen as I noted that all the holes must immersion gold. This is the first time I met a production problem with PCBWay. Ok, I guess there is a first time for everything.

So what to do next? I found there is “Open Dispute” on this order:

 

They have online after-sale system, wow, it’s good. I upload the picture, submit the reason and wait for their reply.

I don’t know how PCBWay generally deals with after-sale issues. To be honest I am a little nervous because I heard usually Chinese companies offer poorly after-sales service. I don’t know whether PCBWay will deal with such a small problem. It will be a loss for them if they reproduce and ship to me.

A few hours later I received emails from their after-sales team:

It’s such a surprise! They took responsibility for their mistakes and reproduce the ruler in 24 hours. From here we can see that PCBWay has very high standards for themselves and care the feeling of clients.

Now I receive the new ruler.

It left a deep impression on me. I don’t think other companies’ after-sales service can compare with PCBWay’s. They are the “Amazon” in PCB prototype and assembly field.

The C.H.I.P Returns, Maybe

Hackaday - ศุกร์, 07/20/2018 - 18:00

Remember the C.H.I.P? The little ARM-based and Linux-capable single board computer that was launched in 2015 at what was then a seemingly impossibly cheap price of $9, then took ages to arrive before fading away and the company behind it going under? Like a zombie, it has returned from the dead!

So, should we be reaching for the staples of zombie movies, and breaking out the long-playing records? Or should we be cautiously welcoming it back into the fold, a prodigal son to the wider family of boards? Before continuing, it’s best to take a closer look.

The C.H.I.P that has returned is a C.H.I.P Pro, the slightly more powerful upgraded model, and it has done so because unlike its sibling it was released under an open-source licence. Therefore this is a clone of the original, and it comes from an outfit called Source Parts, who have put their board up for sale via Amazon, but with what looks suspiciously like a photo of an original Next Thing Co board. We can’t raise Source Parts’ website as this is being written so we can’t tell you much about its originator and whether this is likely to be a reliable supplier that can provide continuity, so maybe we’d suggest a little caution until more information has emerged. We’re sure that community members will share their experiences.

It’s encouraging to see the C.H.I.P Pro return, but on balance we’d say that its price is not the most attractive given that the same money can buy you powerful boards that come with much better support. The SBC market has moved on since the original was a thing, and to make a splash this one will have to have some special sauce that we’re just not seeing. If they cloned the Pocket C.H.I.P all-in-one computer with keyboard and display, now that would catch our attention!

It all seemed so rosy for the C.H.I.P at launch, but even then its competitors doubted the $9 BoM, and boards such as the Raspberry Pi Zero took its market. The end came in March this year, but perhaps there might be more life in it yet.

Thanks [SlowBro] for the tip.

Syndicate content