Though Facebook has been in a bright spotlight since the Cambridge Analytica fallout, it's obviously not the only company that has to deal with issues surrounding how best to protect its users' privacy. That responsibility falls on all tech companies...
People learn in different ways, but sometimes the establishment fixates on explaining a concept in one way. If that’s not your way you might be out of luck. If you have trouble internalizing floating point number representations, the Internet is your friend. [Fabian Sanglard] (author of Game Engine Black Book: Wolfenstein 3D) didn’t like the traditional presentation of floating point numbers, so he decided to explain them a different way.
Instead of thinking of an exponent and a mantissa — the traditional terms — [Fabian] calls the exponent as a “window” that determines the range of the number between two powers of two. So the window could be from 1 to 2 or from 1 024 to 2048 or from 32768 to 65536.
Once you’ve determined the window, the mantissa — [Fabian] calls that the offset — divides the window range into 8,388,608 pieces, assuming a 32-bit float. Just like an 8-bit PWM value uses 128 for 50%, the offset (or mantissa) would be 4,194,304 if the value was halfway into the window.
There are a few details glossed over — the bias in the exponent and the assumed digit in the mantissa are in the provided formulas, but the reason for them isn’t as clearly spelled out as it would be for the “classic” explanation. If you want a go at the traditional classroom lecture on the topic, there’s one below.
In the early 1980s, there were a plethora of 8-bit microcomputers on the market, and the chances are that if you were interested in such things you belonged to one of the different tribes of enthusiasts for a particular manufacturer’s product. If you are British though there is likely to be one machine that will provide a common frame of reference for owners of all machines of that era: The Acorn BBC Microcomputer which was ubiquitous in the nation’s schools. This 6502-driven machine is remembered today as the progenitor and host of the first ARM processors, but at the time was notable for the huge array of built-in interfaces it contained. Its relatively high price though meant that convincing your parents to buy you one instead of a ZX Spectrum was always going to be an uphill struggle.
To be fair, running classic hardware on an FPGA is nothing new and there have been a few BBC Micros implemented in this way, not to mention an Acorn Atom. But this project builds on the previous FPGA BBC Micros by porting it entirely to Verilog and incorporating some of the bug fixes from their various forks. There are screenshots of the result running several classic games, as well as test screens and a benchmark revealing it to be a faithful reproduction of a 2MHz BBC Micro.
In this video, we use a Raspberry Pi Zero W and a Raspberry Pi camera to make a smart security camera! The camera uses object detection (with OpenCV) to send you an email whenever it sees an intruder. It also runs a webcam so you can view live video from the camera when you are away.
Each Friday is PiDay here at Adafruit! Be sure to check out our posts, tutorials and new Raspberry Pi related products. Adafruit has the largest and best selection of Raspberry Pi accessories and all the code & tutorials to get you up and running in no time!
This is the latest version of the Bucket Bot – a mobile PC based robot that can be easily transported in a 5 gallon bucket. The previous one used simple wood based construction. This newer version is based on aluminum and T-Slot, so it is easily expandable.
The bucket bot concept is a vertically oriented robot where all the components are easily accessible. This is superior to the layered approach since you don’t need to unscrew layers to work on the lower level components. This design has the all-important features for mobile robots: a handle and motor power switch!
I also incorporated some new components that make the building easier. There is a little fabrication involved, but it can all be done using hand tools. You can also use a laser cutter for a plastic version of this robot, or use a metal cutting service like the Big Blue Saw if you would like with the included designs.