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On August 2022, I received an email from Offensive Security certifying that I had earned my Offensive Security Certified Professional certificate. [PEN-200] introduces penetration testing tools and techniques via hands-on experience. PEN-200 trains not only the skills, but also the mindset required to be a successful penetration tester. Students who complete the course and pass the exam earn the coveted Offensive Security Certified Professional (OSCP) certification. This was one of the most meaningful certificates I have earned to date, and I’m really proud to have earned it. I learned a lot throughout this journey, and I tried to consolidate my thoughts below in hopes it will be useful to others. I think I also offer the unique perspective of going through the course twice over a number of years. ...

I’ve posted about Scaleway multiple times raising their prices and big surprise they have done it again. Don’t be fooled by the drop in price of PAR3 as it provides the most expensive instances and is subject to special pricing. And Scaleway may remove the 50% discount in half a year. Bus App, ReduxWhat came from the cloud, goes back to the cloud. Migrating the bus app from the server back to the cloud!West Side Electronics·Benjamen Lim Multiple price increases (3!) over a period of a two years is unusual because it makes it hard to judge and prepare expenses. Companies don’t do this lightly because it sends the message that the price can be increased whenever they want, which creates nervous customers who may look for more stable pricing elsewhere. For things like infrastructure, that makes it even more pressing as migration is expensive and difficult. ...

The most salvagable part of A DC motor typically just spins when you apply voltage to it. But when you carefully control that voltage, and have access to an encoder attached to the motor, you can add some intelligence to the motor and do some very interesting things with it: like making it go to a precise position. Obstruction to show position control and not just a timer-based control And combining that with one of the cheapest microcontrollers in the world makes it a little more fun, because now you can add a digital interface to the motor that allows any other modern microcontroller to easily command the motor for the cost of a single piece of tissue paper. ...

Even in the world of microcontrollers, a $0.03 microcontroller in single units is an oddity. It is very cheap. The cheapest microcontrollers you can find in single units among online distributors like Digikey or Mouser are in the region of $1. To push it below the $1 mark, your order usually has to be in the thousands. Putting it into perspective, it is a no-name smartphone for $6 in a world of $600 smartphones. ...

To buy or to build is all about the tradeoffs in light of unknowns: if you buy, you can get the product you need faster, but you sacrifice flexibility later on. You also have to consider ecosystem lock-in and being forced to build hacky workarounds to get the functionality you want. If the project turns out to be massively successful and you need a custom application, tearing down everything and rebuilding from scratch can be very painful. ...

How I built a great tool for IoT prototyping: a self-powered, wireless measurement device that measures voltage and current. GitHub - benlhy/wireless_measurements: Simple, Compact Wireless MeasurementSimple, Compact Wireless Measurement. Contribute to benlhy/wireless_measurements development by creating an account on GitHub.Git·Hubbenlhy Hardware Repo The Gist IoT devices have two big constraints: they are wireless, which draws power, and they are often battery powered, which means that they don’t have much power to draw upon. Managing the power draw then becomes an important feature in any IoT project. I built a device that can help me do exactly that. ...

Prerequisites Install Inkscape Download SVG2Shenzhen - https://github.com/badgeek/svg2shenzhen Install Follow the instructions on installing SVG2Shenzhen to Inkscape. Use SVG2Shenzhen allows you to create vector drawings on multiple layers of KiCAD. Start at 1. Prepare Document where you select the layers that SVG to Shenzhen will add to your module. Draw on each layer as needed Go to 2. Export to KiCAD - select the folder that you want to save the module to, and save as module. Leave the other options at default values. Hit apply. Open KiCAD, and add the Module as the footprint library under preferences Go to PCBnew and add the footprint of the image to the board. And that’s it! ...

In 2020 what I managed to do: Learned D3 through two applications: building a binary tree and a most commonly paired ingredients graphic. Finally gained a toehold in understanding Javascript frontend technologies React and Vue through building a few different services: a bus arrival page, a page that ranks my tea preferences based on weighted factors, and a display page for my home automation network. Built a Bus Arrival App that serves as a testbed for learning new technologies. Finally started to understand how backend services work by building a NodeJS app to handle data for the Bus Arrival App. Implemented my first serverless function for the Bus Arrival App because I didn’t need a whole VM just to run a script. Built an understanding of how Bluetooth Low Energy works by building a wireless soil sensor and integrated it with a NodeJS backend that collects the information with a Python script and posts it to InfluxDB which then displays it on a Vue app. Tore apart a few things to find out how they worked: A table lamp, a wireless switch from IKEA, another wireless control from IKEA. Investigated low power and energy harvesting options for devices that have to live without grid power for a long time. Built a soil sensing circuit to monitor the health of several plots wirelessly Designed a pretty Chicago ‘L’ PCB that reflects when the trains move in and out of the station. This year has been heavily focused on software and electronics.

In my quest to achieve True Wireless™, I recently got interested in cellular modules because they provide the ultimate in wireless connectivity - there are no modems and no routers required. I thought searching for a cellular module would be like any other wireless technology that I’m familiar with: start from the hobby-level products from Adafruit and Sparkfun and gradually work my way backwards to discover what are the best cellular modules based on observed usage in other products. This method saves me a lot of time and effort in narrowing down the selection choice. ...

I recently ran into an issue where my code stopped compiling after I added a few new features. After some digging, I realized that KEIL was complaining that the evaluation license that I was using was not valid because the CID code no longer matched, and the code was too big for the evaluation license. After some digging around I found that if some of your parameters have changed since you applied for the license (like if you updated your computer), then it is possible that the error could occur. Licensing User’s Guide: Licensing Errors ...