application

7 Articles

Blinkenlights To Bootloader: A Guide To STM32 Development

August 6, 2023 by 15 Comments

While things like the Arduino platform certainly opened up the gates of microcontroller programming to a much wider audience, it can also be limiting in some ways. The Arduino IDE, for example, abstracts away plenty of the underlying machinations of the hardware, and the vast amount of libraries can contribute to this effect as well. It’s not a problem if you just need a project to get up and running, in fact, that’s one of its greatest strengths. But for understanding the underlying hardware we’d recommend taking a look at something like this video series on the STM32 platform.

The series comes to us from [Francis Stokes] of Low Byte Productions who has produced eighteen videos for working with the STM32 Cortex-M4 microcontroller. The videos start by getting a developer environment up and blinking LEDs, and then move on to using peripherals for more complex tasks. The project then moves on to more advanced topics and divides into two parts, the development of an application and also a bootloader. The bootloader begins relatively simply, and then goes on to get more and more features built into it. It eventually can validate and update firmware, and includes cryptographic signing (although [Francis] notes that you probably shouldn’t use this feature for production).

One of the primary goals for [Francis], apart from the actual coding and development, was to liven up a subject matter that is often seen as dry, which we think was accomplished quite well. A number of future videos are planned as well. But, if you’re not convinced that the STM32 platform is the correct choice for you, we did publish a feature a while back outlining a few other choices that might provide some other options to consider.

Continue reading “Blinkenlights To Bootloader: A Guide To STM32 Development” →

Computer Speed Gains Erased By Modern Software

July 2, 2023 by 284 Comments

[Julio] has an older computer sitting on a desk, and recorded a quick video with it showing how fast this computer can do seemingly simple things, like open default Windows applications including the command prompt and Notepad. Compared to his modern laptop, which seems to struggle with even these basic tasks despite its impressive modern hardware, the antique machine seems like a speed demon. His videos set off a huge debate about why it seems that modern personal computers often appear slower than machines of the past.

After going through plenty of plausible scenarios for what is causing the slowdown, [Julio] seems to settle on a nuanced point regarding abstraction. Plenty of application developers are attempting to minimize the amount of development time for their programs while maximizing the number of platforms they run on, which often involves using a compatibility layer, which abstracts the software away from the hardware and increases the overhead needed to run programs. Things like this are possible thanks to the amount of computing power of modern machines, but not without a slight cost of higher latency. For applications developed natively, the response times would be expected to be quite good, but fewer applications are developed natively now including things that might seem like they otherwise would be.  Notepad, for example, is now based on UWP.

While there are plenty of plausible reasons for these slowdowns in apparent speed, it’s likely a combination of many things; death by a thousand cuts. Desktop applications built with a browser compatibility layer, software companies who are reducing their own costs by perhaps not abiding by best programming practices or simply taking advantage of modern computing power to reduce their costs, and of course the fact that modern software often needs more hardware resources to run safely and securely than equivalents from the past.

SheepShaver: A Cross-Platform Tool For Retro Enthusiasts

March 24, 2023 by 20 Comments

The world of desktop computing has coalesced into what is essentially a duopoly, with Windows machines making up the bulk of the market share and Apple carving out a dedicated minority. This relatively stable state hasn’t always existed, though, as the computing scene even as late as the 90s was awash with all kinds of competing operating systems and various incompatible hardware. Amiga, Unix, OS/2, MacOS, NeXT, BeOS, as well as competing DOSes, were all on the table at various points.

If you’ve still got a box running one of these retro systems, SheepShaver might be able to help expand your software library. It’s not the sort of virtualization that we’re used to in the modern world, with an entire operating system running on a sanctioned-off part of your system. But SheepShaver does allow you to run software written for MacOS 7.5.2 thru 9.0.4 in a different environment. Unix and Linux are both supported, as well as Mac OS X, Windows NT, 2000, and XP, and the enigmatic BeOS. Certain configurations allow applications to run natively without any emulation at all, and there is plenty of hardware support built-in as well.

For anyone running retro hardware from the late 90s or early 00s, this could be just the ticket to get an application running that wasn’t ever supported on one of these machines. As for the name, it’s a play on another piece of software called ShapeShifter which brought a Mac-II emulator to the Amiga. SheepShaver has been around since the late 90s, too, so we’re surprised that we haven’t featured it before since it is such a powerful tool for cross-platform compatibility for computers of this era. Even if all you are hanging on to is an old BeBox.

Applications For The Bitcoin Blockchain

October 27, 2015 by 34 Comments

Bitcoin, the libertarian’s dream currency, is far past the heady days of late 2013. When one Bitcoin was worth $1000 USD, there was no end to what could be done; new, gigantic mining rigs were being created, every online store jumped onto the bandwagon, and the price of Bitcoin inevitably crashed. Right now, the exchange rate sits at about $280 USD per coin, valuing all the Bitcoins ever mined somewhere around $4 Billion USD. That’s a lot of coins out there, and a lot of miners constantly verifying the integrity of the greatest thing to come from the Bitcoin community: the blockchain.

The bitcoin is just a record, or the ledger, of every transaction that has ever occurred on the Bitcoin network. It’s distributed, and the act of mining coins creates new blocks, or another set of data committed to the blockchain for eternity. While magical Internet money™ is by far the most visible product of the blockchain, developers, investors, and other people in the know are gushing about the possibilities of what can be done with a distributed record that can’t practically be altered and can’t be deleted.

[Jon Matonis], a figurehead for the entire cryptocurrency movement, recently said Bitcoin has become the strongest computer in the world, and stronger than all of the top 500 supercomputers combined. All of this computational power is effectively funneled in to verifying the integrity of the blockchain.

Bitcoin and other cryptocurrencies are not just a completely anonymous payment system; that’s only a side effect of the blockchain. The blockchain is the only inherently valuable part of a bitcoin; each transaction is logged in the blockchain, providing incredible security over how every coin is spent. No currency in the history of mankind has ever had a record of how every dollar or denarius is spent, and at the very least makes for very interesting economics research. Now, thousands of researchers across the globe are wondering what else the blockchain can do; tapping the power of the most powerful computer on the planet must have some interesting applications, and in the last few months, a few ideas have popped up.

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Wildlife Camera

Remote Controlled Wildlife Camera With Raspberry Pi

April 8, 2015 by 21 Comments

If you are interested in local wildlife, you may want to consider this wildlife camera project (Google cache). [Arnis] has been using his to film foxes and mice. The core components of this build are a Raspberry Pi and an infrared camera module specifically made for the Pi. The system runs on a 20,000 mAh battery, which [Arnis] claims results in around 18 hours of battery life.

[Arnis] appears to be using a passive infrared (PIR) sensor to detect motion. These sensors work by detecting sudden changes in the amount of ambient infrared radiation. Mammals are good sources of infrared radiation, so the sensor would work well to detect animals in the vicinity. The Pi is also hooked up to a secondary circuit consisting of a relay, a battery, and an infrared light. When it’s dark outside, [Arnis] can enable “night mode” which will turn on the infrared light. This provides some level of night vision for recording the furry critters in low light conditions.

[Arnis] is also using a Bluetooth dongle with the Pi in order to communicate with an Android phone. Using a custom Android app, he is able to connect back to the Pi and start the camera recording script. He can also use the app to sync the time on the Pi or download an updated image from the camera to ensure it is pointed in the right direction. Be sure to check out the demo video below.

If you like these wildlife cameras, you might want to check out some older projects that serve a similar purpose. Continue reading “Remote Controlled Wildlife Camera With Raspberry Pi” →

Facebook Photo Hack

Exposing Private Facebook Photos With A Malicious App

March 20, 2015 by 21 Comments

[Laxman] is back again with another hack related to Facebook photos. This hack revolves around the Facebook mobile application’s “sync photos” function. This feature automatically uploads every photo taken on your mobile device to your Facebook account. These photos are automatically marked as private so that only the user can see them. The user would have to manually update the privacy settings on each photo later in order to make them available to friends or the public.

[Laxman] wanted to put these privacy restrictions to the test, so he started poking around the Facebook mobile application. He found that the Facebook app would make an HTTP GET request to a specific URL in order to retrieve the synced photos. This request was performed using a top-level access token. The Facebook server checked this token before sending down the private images. It sounds secure, but [Laxman] found a fatal flaw.

The Facebook server only checked the owner of the token. It did not bother to check which Facebook application was making the request. As long as the app had the “user_photos” permission, it was able to pull down the private photos. This permission is required by many applications as it allows the apps to access the user’s public photos. This vulnerability could have allowed an attacker access to the victim’s private photos by building a malicious application and then tricking victims into installing the app.

At least, that could have been the case if Facebook wasn’t so good about fixing their vulnerabilities. [Laxman] disclosed his finding to Facebook. They had patched the vulnerability less than an hour after acknowledging the disclosure. They also found this vulnerability severe enough to warrant a $10,000 bounty payout to [Laxman]. This is in addition to the $12,500 [Laxman] received last month for a different Facebook photo-related vulnerability.

C Sharp Development 101 – Part 2: Toolbox Controls

October 15, 2010 by 29 Comments
In this tutorial we are going to start finding out more about the toolbox we utilized in the previous tutorial.  The Controls available in the toolbox are quite extensive and allow users to simplify a variety of everyday tasks such as manually creating and instantiating a textbox on a windows form.  At the end of this tutorial you should be comfortable finding Controls in the Visual Studio Toolbox, alter or produce code to link tools together using event handlers and ultimately get a better sense of Visual Studio, it’s layout and how to easily navigate it.