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Motherboard, videocard, memory and so on

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Journey to find a headset with a good side talk cancellation mic for calls in an open office

Level of difficulty Easy
Reading time 6 min
Views 2.7K

TL;DR: All AI-based noise cancellations suck, only the physical cancellation technique works! And physical cancellation is implemented well only in Jabra devices yet, but other features suck them! All Bluetooth headsets suck too! So, no solution yet, just complaints!

The environment: I work in a pretty talky office room, where sit around 10 people, and all of them have many online conferences every day, including me. So, silence in the room is a rare situation.

The problem: The main problem is that most of the microphones pick up all side talk pretty loud, which makes it very unpleasant for other people to listen to my voice in meetings!

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Total votes 1: ↑1 and ↓0 +1
Comments 12

Controlling Brushless Motors using a Linux computer or a PLC

Reading time 5 min
Views 2.5K

In this video, we will look at how to connect brushless motor controllers to a Linux computer. Specifically, we will use a computer running Debian. The same steps would work for Ubuntu Linux and other Linux distributions derived from Debian.

I've got a small sensorless brushless motor, and a bigger brushless motor with a built-in absolute encoder. Lets look at how to control those from my Debian Linux computer. Servosila brushless motor controllers come in several form factors with either a circular or a rectangular shape. The controllers come with a set of connectors for motors and encoders as well as for USB or CANbus networks.

The controllers can be powered by a power supply unit or by a battery. To spice up my setup, I am going to use a battery to power the controllers and thus their motors. The controllers need 7 to 60 volts DC of voltage input. If I connect the battery, the controllers get powered up. The small LED lights tells us that the controllers are happy with the power supply.

We need to connect the brushless motor controllers to the Linux computer. There are two ways to do that - via CANbus or via USB. Lets look at the USB option first. A regular USB cable is used. Only one of the controllers needs to be connected to a computer or a PLC.

Next, we need to build an internal CANbus network between the controllers. We are going to use a CANbus cross-cable to interconnect the controllers. Each controller comes with two identical CANbus ports that help chain multiple controllers together in a network. If one of the interconnected brushless motor controllers is connected to a computer via USB, then that particular controller becomes a USB-to-CANbus gateway for the rest of the network. Up to 16 controllers can be connected this way via a single USB cable to the same control computer or a PLC. The limit is due to finite throughput of the USB interface.

Video & Read more
Total votes 4: ↑3 and ↓1 +2
Comments 0

Passcode Data Protection by Using FPGA and Verilog

Reading time 4 min
Views 2.7K

There are many situations when you need to protect your data, and different tools can be used to do that. For example, a safe. We develop a passcode data protection mechanism by using an FPGA board and Quartus Prime software. It allows demonstrating the basic concepts of a combination lock such as entering data, setting and checking a passcode, and displaying data.

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Total votes 5: ↑3 and ↓2 +1
Comments 0

Playing with Nvidia's New Ampere GPUs and Trying MIG

Reading time 11 min
Views 3.8K


Every time when the essential question arises, whether to upgrade the cards in the server room or not, I look through similar articles and watch such videos.


Channel with the aforementioned video is very underestimated, but the author does not deal with ML. In general, when analyzing comparisons of accelerators for ML, several things usually catch your eye:


  • The authors usually take into account only the "adequacy" for the market of new cards in the United States;
  • The ratings are far from the people and are made on very standard networks (which is probably good overall) without details;
  • The popular mantra to train more and more gigantic models makes its own adjustments to the comparison;

The answer to the question "which card is better?" is not rocket science: Cards of the 20* series didn't get much popularity, while the 1080 Ti from Avito (Russian craigslist) still are very attractive (and, oddly enough, don't get cheaper, probably for this reason).


All this is fine and dandy and the standard benchmarks are unlikely to lie too much, but recently I learned about the existence of Multi-Instance-GPU technology for A100 video cards and native support for TF32 for Ampere devices and I got the idea to share my experience of the real testing cards on the Ampere architecture (3090 and A100). In this short note, I will try to answer the questions:


  • Is the upgrade to Ampere worth it? (spoiler for the impatient — yes);
  • Are the A100 worth the money (spoiler — in general — no);
  • Are there any cases when the A100 is still interesting (spoiler — yes);
  • Is MIG technology useful (spoiler — yes, but for inference and for very specific cases for training);
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Total votes 5: ↑5 and ↓0 +5
Comments 0

Hypercube. How we gave developers test devices without losing any

Reading time 11 min
Views 4.8K
You can’t properly test and debug mobile apps without test devices, which there should be plenty of considering how the same code may behave differently on different models. So how do we keep track of these devices? How do we quickly provide developers and testers with the smartphones they need, configured the way they need, and without much red tape?

I’m Alexey Lavrenuke. Over the years, I’ve worn many hats: one of the authors behind Yandex.Tank, a speaker on load testing, and the guy who calculated energy consumption by mobile phones. Now I’m a Yandex.Rover developer on the self-driving car team.

After the phones and before Yandex.Rover, there was Hypercube.

A few years ago, the head of mobile development popped in to the load testing department and mentioned a problem they were having with test devices: phones had a tendency to inexplicably migrate from one desk to another. Picking the right device and then finding it had become a challenge. We already experienced working with mobile devices from building a digital ammeter to calculate energy consumption, so we decided to help our coworkers out and quickly rig up a handy contraption. We figured the whole thing wouldn’t take more than three months. Oh how wrong we were. Let me tell you what we were really in for.


''Dallas cube''
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Total votes 13: ↑12 and ↓1 +11
Comments 2

Writing a laptop driver for fun and profit, or How to commit to kernel even if you're not that smart

Reading time 5 min
Views 2.6K

Where it all began


Let’s start with our problem statement. We have 1 (one) laptop. A new, gamer laptop. With some RGB-backlight on its keyboard. It looks like this:

image
Picture taken from lenovo.com

There’s also a program installed on this laptop. That’s the thing that controls our backlight.

One problem – the program runs under Windows, and we want everything to work on our favourite Linux. Want LEDs to flash and those pretty colours to blink on and off and such. A natural question arises, can we do all that without reverse-engineering and writing our own drivers?

A natural answer arises, no. Let’s open IDA and get cracking.

Read more →
Total votes 5: ↑5 and ↓0 +5
Comments 0

AHURATUS Smart Home Voice Assistant

Reading time 7 min
Views 1.8K

N|Solid


N|Solid


AHURATUS Smart Home Voice Assistant


Developed by Ehsan Shaghaei
Innopolis University
AHURATUS Scientific Club.

STM32F103ZET6 UNIVERSAL BOARD


Introduction


AHURATUS Smart Home Voice Assistant is an IOT device developed in order to control other home devices by voice detection. Note: This device is made ONLY for academic purposes.


Approach


Description


"AHURATUS Smart Home Voice Assistant" uses an ARM Cortex-M3 process for running the instructions as well as several peripheral devices in order to decrease the complexity of data bus and RF-Circuit calculations.


Bill of Materials


# Component Name Role Technical Document links
1 STM32F103ZET6 Process and Control Datasheet
2 HC-05 Bluetooth Module Bluetooth Radio Connection Datasheet
3 220-5V AC-DC Adapter Powering the circuit Datasheet
4 LED or Mosfets or Relays To System Output Datasheet
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Total votes 14: ↑14 and ↓0 +14
Comments 1

Optimising server distribution across the racks

Reading time 5 min
Views 1.8K
Recently, a colleague asked me in a chat:

— Is there an article how to pack servers into the racks properly?

I realised that I'm unaware of it. So, I decided to write my text.

Firstly, this is an article about bare metal servers in the data centre (DC) facilities. Secondly, we estimate that there are a lot of servers (hundreds or thousands); the article doesn't make sense for fewer quantities. Thirdly, we consider that there are three constraints in the racks: physical space, electric power per each one, and cabinets stay in the rows adjacent to each other, so we can use a single ToR switch to connect servers in them.
The answer to the original question depends significantly...
Total votes 11: ↑10 and ↓1 +9
Comments 0

TOKEN2 Molto-1, world's first multi-profile TOTP hardware token

Reading time 3 min
Views 1.5K
[Update 15/09/2020: Molto2 is coming]

imageOur new product currently being finalized, the Token2 Molto-1, will expand on our technology by now supporting up to 10 Time based One-Time Password (TOTP) profiles. Earlier this year, with the miniOTP-2, miniOTP-3, and C301 we introduced the world’s first programmable TOTP tokens with time sync. The aim of these products was to provide a solution to the time drift that affects hardware tokens. We didn’t want to stop there, though! We also recognize the desire for multiple profiles which is why our latest product is a programmable multi-profile hardware token, called Token2 Molto-1. The clue is in the name, at least for anyone who understands Italian — “molto” is “many” in Italian. Having a multi-profile programmable hardware token means you can have only one device for up to 10 of your accounts.
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Total votes 4: ↑3 and ↓1 +2
Comments 6

Tech Insights: Are LED filament-lamps so good?

Reading time 8 min
Views 3.7K
Saluting my LED lamp fans!

Today we will talk about the palpitating and extremely popular subject in recent years — filament LED (Light-Emitted Diode) lamps. Numerous articles have been published here on Habr (1, 2, 3) and on the web, but none of them tells us a word about in-depth analysis of the lamps (what is actually inside) and comparison of their temperature characteristics. Therefore, especially for you — my dear LED-lovers — I conducted a detailed analysis of such lamps from different manufacturers, including temperature measurement of LEDs themselves.

Afterwards we will try to answer the question: are filament lamps as good as marketers present them to us?

Disclaimer: this is my very first attempt to translate and adopt an article from Habr into English, so I will ask you to give a fruitful feedback and correct some mistake if any present.
Shock, thrill and scandals!
Total votes 9: ↑8 and ↓1 +7
Comments 0

Independent Tests of Baikal-T1 — the first Russia's 28 nm SoC — and BFK 3.1 Evaluation Board

Reading time 10 min
Views 6.1K
Tech journalist Igor Oskolkov of 3DNews.ru has recently tested publicly available version of the evaluation board or, as the vendor calls it, the developer software-hardware complex, under the code name BFK 3.1 with the Russian SoC Baikal-T1 based on the MIPS P5600 Warrior architecture. Here goes the English translation of his text, that was first published in Russian by servernews.ru.
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Total votes 21: ↑20 and ↓1 +19
Comments 2

Flightradar24 — how does it work?

Reading time 4 min
Views 122K
I’m going to hazard a guess and say that everyone whose friends or family have ever flown on a plane, have used Flightradar24 — a free and convenient service for tracking flights in real time.



But, if my friends are any indication, very few people know that the service is community-driven and is supported by a group of enthusiasts gathering and sending data. Even fewer people know that anyone can join the project — including you.

Let’s see how Flightradar and similar other services works.
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Total votes 80: ↑79 and ↓1 +78
Comments 12

System in Package, or What's Under Chip Package Cover?

Reading time 7 min
Views 5K
Transistor feature size is decreasing despite constant rumors about the death of Moore’s law and the fact that industry is really close to physical limits of miniaturisation (or even went through them with some clever technology tricks). Moore’s law, however, created user’s appetite for innovation, which is hard to handle for the industry. That’s why modern microelectronic products aren’t just feature size scaled, but also employ a number of other features, often even more complicated than chip scaling.


Disclaimer: This article is a slightly updated translation of my own piece published on this very site here. If you're Russian-speaking, you may want to check the original. If you're English-speaking, it's worth noting that English is not my native language, so I'll be very grateful for the feedback if you find something weird in the text.
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Total votes 38: ↑38 and ↓0 +38
Comments 0

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