Usually when we visited lectures the notes and explanations where given on a chalk board or a projector. With the lecturer looking away from the audience most of the time.
This is where Light Boards come in handy. They allow the lecturer to face his audience and give explanations on a board…
I was made aways by Ryan Heffernans tweet on the project he did together with his son. He built one of these light boards! The short clip above shows his son on their board.
My son and I built a lightboard. You write on it like a whiteboard, but you can face your audience and the writing is illuminated. Commercial versions cost around $10k, but we made ours for $400 in parts from Home Depot. Here’s how.
You might have asked yourself how it is that some phones charge up faster than others. Maybe the same phone charges at different speed when you’re using a different cable or power supply. It even might not charge at all.
There is some very complicated trickery in place to make those cables and power supplies do things in combination with the active devices like phones. Many of this is implemented by standards like “Quick Charge”:
Quick Charge is a technology found in QualcommSoCs, used in devices such as mobile phones, for managing power delivered over USB. It offers more power and thus charges batteries in devices faster than standard USB rates allow. Quick Charge 2 onwards technology is primarily used for wall adaptors, but it is also implemented in car chargers and powerbanks (For both input and output power delivery).
So in a nutshell: If you are able to speak the quick charge protocol, and with the right cable and power supply, you are able to get anything between 3.6 and 20V out of such a combination by just telling the power supply to do so.
This is great for maker projects in need of more power. There’s lots of things to consider and be cautious about.
We’ve got several quite big fish tanks in our house. Mainly used by freshwater turtles.
These turtles need to be fed every once in a while. And while this is not an issue normally it’s an issue if you leave the house for travel for an extended period of time.
Of course there are humans checking on everything in the house regularly but as much as can be automated should and will be automated in our household. So the requirement wa to have the turtle feeding automated.
To achieve this is would be necessary to have a fixed amount of turtle food be dispensed into the tanks on a plan and with some checks in the background (like water quality and such).
It’s been quite a hassle to come up with a plan how the hardware should look like and work. And ultimately i’ve settled on retrofitting an off-the-shelf fish pond feeder to become controllable through MQTT.
The pond feeder I’ve found and used is this one:
It’s not really worth linking to a specific product detail page as this sort of feeder is available under hundreds of different names. It always looks the same and is priced right around the same.
If you want to build this yourself, you want one that looks like the above. I’ve bought 3 of them and they all seem to come out of the same factory somewhere in China.
Anyway. If you got one you can easily open it up and start modifying it.
The functional principle of the feeder is rather simple:
turn the feeder wheel
take the micro-switch status in account – when it’s pressed down the wheel must be pushing against it
turn it until the micro-switch is not pressed anymore
turn some more until it’s pressed again
Simple. Since the switch-status is not known on power loss / reboot a calibration run is necessary (even with the factory electronics) every time it boots up.
After opening the feeder I’ve cut the two cables going to the motor as well as the micro-switch cables. I’ve added a 4-Pin JST-XH connector to both ends. So I can reconnect it to original state if desired.
These are all the parts needed:
I am using a Wemos D1 Mini and a couple of additional components apart from the prototype board:
A PN2222 NPN transistor, a rectifier diode 1N4007 and a 220 Ohm resistor.
I’ve connected everything according to this schematic I’ve drawn with Fritzing:
I’ve then prototyped away and put everything on the PCB. Of course with very limited solderig skill:
As you can see the JST-XH connector on Motor+Switch can now be connected easily to the PCB with all the parts.
Make sure you check polarity and that you did correctly hook up the motor and switch.
When done correctly the PCB (I’ve used 40mm x 60mm prototype pcb) and all cables will fit into the case. There’s plenty of room and I’ve put it to the side of it. I’ve also directly connected an USB cable to the USB port of the Wemos D1 Mini. As long as you put at least 1A into it it will all work.
Since the Wemos D1 Mini sports an ESP8266 and is well supported by Arduino it was clear to me to use Arduino IDE for the software portion of this project.
To get everything running you need to modify the .ino file in the src folder like so:
What you need to configure:
the output pins you have chosen – D1+D2 are pre-configured
WiFi SSID + PASS
MQTT Server (IP(+Username+PW))
MQTT Topic prefix
Commands that can be sent through mqtt to the /feed topic.
MQTT topics and control
There are overall two MQTT topics:
$prefix/feeder-$chipid/state This topic will hold the current state of the feeder. It will show a number starting from 0 up. When the feeder is ready it will be 0. When it’s currently feeding it will be 1 and up – counting down for every successfull turn done. There is an safety cut-off for the motor. If the motor is longer active than configured in the MaximumMotorRuntime variable it will shut-off by itself and set the state to -1.
$prefix/feeder-$chipid/feed This topic acts as the command topic to start / control the feeding process. If you want to start the process you would send the number of turns you want to happen. So 1 to 5 seems reasonable. The feeder will show the progress in the /state topic. You can update the amount any time to shorten / lengthen the process. On the very first feed request after initial power-up / reboot the feeder will do a calibration run. This is to make sure that all the wheels are in the right position to work flawlessly.
Augmented Reality – AR – is getting some buzz here and there throughout the last 20 years almost. With hardware becoming more powerful and optics+light hardware becoming cheaper and more efficient it’s still all but close to become widely used and available.
Many refer to some one-trick pony feature in location-based games like “Pokemon Go” to being “AR”. But actual useful cases of AR are there but not feasible with current hardware generations.
Nevertheless a team in california has taken our the scissors and keyboards and made HoloKit:
HoloKit features super sharp optics quality and a 76-degree diagonal field of view. Pairing with a smartphone, HoloKit can perform an inside out tracking function, which uses the changing perspective on the outside world to note changes in its own position. HoloKit merges the real and the virtual in a smart way. While you see through the real world, virtual objects are blended into it. Powered by the accurate gyro and camera on smart phones, HoloKit solidly places virtual objects onto your table or floor, as if they were physically there without physical makers. These virtual objects will stay in the same place even if you walk away, just like real physical objects.
HoloKit is different from screen-based AR experience like Tango. You can directly see through the headset and view the real world as is, and in the meantime the virtual objects are projected on top of the real world, as opposed to viewing both the real and the virtual through a smartphone camera.
After my first stationary trainer broke I bought a new one with the capability to measure wattage and also to apply resistance measured by the watt.
After looking at my average speeds, heart-rates and times on the device I was able to build a quite detailed understanding of the broader picture. What effects my power output and what does not. The effects of nutrition and health to what the body will deliver while being asked the exact same power output curve than the last time.
In a nutshell the numbers tell me that I am usually at a mediocre wattage of 150W constant load doing about 40 km/h average. My reserves usually allow me to go for 1-2 hours without a break doing this.
So far so good. Now I’ve found out from more serious cyclers that there’s something like “Functional Threshold Power“. I do regular have tests at the doctors to check for any heart-rate issues.
Reading about this Functional Threshold Power my curiousity is sparked.
How much could I do? Should I even go for measuring it?
Maybe you want to give EasyEDA a try as it’s in-browser experience is better than anything I had come across so far. Granted I am not doing PCBs regularly but nevertheless – whenever I tried with the programs I’ve got recommended it wasn’t as straight forward as it is with this tool.
When you are writing code the patterns seem to repeat every once in a while. Not only the patterns but also the occasion you are going to apply certain code styles and methods while developing.
To support a developer with this creative work the tedious and repetitious tasks of typing out what is thought can be supported by machine learning.
Chances are your favourite IDE already supports an somehow AI driven code autocomplete feature. And if it does not, read on as there are ways to integrate products like TabNine into any editor you can think of…
Visual Studio IntelliCode is a set of AI-assisted capabilities that improve developer productivity with features like contextual IntelliSense, argument completion, code formatting, and style rule inference.
Of course there are some new contenders to the scene, like TabNine:
TL;DR: TabNine is an autocompleter that helps you write code faster. We’re adding a deep learning model which significantly improves suggestion quality. You can see videos below and you can sign up for it here.
Deep TabNine requires a lot of computing power: running the model on a laptop would not deliver the low latency that TabNine’s users have come to expect. So we are offering a service that will allow you to use TabNine’s servers for GPU-accelerated autocompletion. It’s called TabNine Cloud, …
Preserving old software is all about storing it and keeping it running.
With the most important part being the later one. The best way to keep things running is by emulating the old and obsolete hardware as accurate as possible.
In computing, an emulator is hardware or software that enables one computer system (called the host) to behave like another computer system (called the guest). An emulator typically enables the host system to run software or use peripheral devices designed for the guest system. Emulation refers to the ability of a computer program in an electronic device to emulate (or imitate) another program or device.
There are a lot of different types of emulators for all sorts of purposes.
There’s things like bochs which is effectively emulating the hardware of a PC on chip-level and can run virtually anywhere:
Bochs is a highly portable open source IA-32 (x86) PC emulator written in C++, that runs on most popular platforms. It includes emulation of the Intel x86 CPU, common I/O devices, and a custom BIOS. Bochs can be compiled to emulate many different x86 CPUs, from early 386 to the most recent x86-64 Intel and AMD processors which may even not reached the market yet.
Emulators of game consoles are alike that – they are emulating the whole system hardware and are able to run original and unchanged code by replicating the exact hardware. Sometimes more and sometimes less exactly.
Hardware emulation in itself an extremely interesting field of software engineering. There’s the hard way to emulate everything accurately (and slowly) by doing what the actual old hardware would have done but maybe in software (or even in replicated hardware).
In regards of old game console hardware there are even now specialized distributions of lots of hardware/system emulators available for specific and readily available hardware like the RaspberryPi. Some of them recently have gotten some nice updates.
The firecracker exploded. Apparently after 2 weeks of usage of the Chuwi Hi10 Air the eMMC flash is malfunctioning.
In a totally strange way: Every byte on the eMMC can be read, seemingly. Even Windows 10 boots. But after a while it will hang and blue screen. Apparently because it tries to write to the eMMC and when those writes fail and pile up in the caches at some point the system calls it quits.
Anyhow: It means that no byte that is right now on this eMMC can be deleted / overwritten but only be read.
The great chinese support is really helpful and offered to replace the device free of charge right away. That’s very nice! But I came to the conclusion that I cannot send the device in, because:
It contains a full set of synched private data that I cannot remove by all means because the freaking soldered-on eMMC flash is broken.
The recipient of this broken tablet in china would be able to read all my data and I could not do anything about it.
Only an extremely small fraction of data is on there unencrypted. Only that much I hadn’t yet switched on encryption on during the initial set-up I was still doing on the device. And that little piece of data already is what won’t let me send out the device.
Now, what can we learn from this? We can learn: Never ever ever work with anything, even during set-up, without full encryption.
In 2007 I had become proud owner of a Samsung ML-2010 mono laser printer. It’s done a great job ever since and I can recall changing the toner just once so far.
So you can tell: I am not a heavy printer user. Every so often I gotta print out a sheet of paper to put on a package or to fill out a form. A laser printer is the perfect fit for this pattern as it’s toner is not going-bad or evaporating like ink does in ink-printers.
So I still like the printer and it’s in perfect working condition. I’ve just recently filled up the toner for almost no money. But – but this printer needs to be physically connected to the computer that wants to print.
As the usage patterns have significantly changed in the last 12 years this printer needs to be brought into todays networked world.
Replacing it with a new printer is not an option. All printers I could potentially purchase are both more expensive to purchase and the toner is much more expensive to refill. No-can-do.
If only there was an easy way to get the printer network ready. Well, turns out, there is!
First let’s start introducing an opensource project: CUPS
CUPS (formerly an acronym for Common UNIX Printing System) is a modular printing system for Unix-like computer operating systems which allows a computer to act as a print server. A computer running CUPS is a host that can accept print jobs from client computers, process them, and send them to the appropriate printer.
The franchise was started by Kow Yokoyama in the 1980’s. Yokoyama-san was a scratch-build modeller, artist and sculptor. Among his works he built machines of war that would fight in the 29th century, but took their visual cues from early 19th century weaponry and the early NASA space program. All his models were pieced together from numerous kits including armor, aircraft, cars and found objects (like ping pong balls).
With recent announcements around human brain and brain-machine interface research like Neuralink the topic is seemingly seeing some more investments now.
As this whole topic is special to my heart I am interested in all things brain simulations. Thus here’s my personal “logbook entry” on the re-appearance of this topic:
This leads to one of the arguments for whole-brain simulation: it’ll help us solve the “biological imitation game,” a Turing test-like assay that pits digitally reconstructed brains against real ones. Iterations of the test help select increasingly more accurate models for a given task, which eventually become the most promising ideas for how specific biological networks operate. And because these models are based on mathematical equations, they could become the heart of next-generation AI.
A visualization of my son’s sleep pattern from birth to his first birthday. Crochet border surrounding a double knit body. Each row represents a single day. Each stitch represents 6 minutes of time spent awake or asleep
If you ever want to quickly explain what augmented reality could be to a person not knowing yet, you might want to use this (and other) use cases for a visual explanation:
I achieved this by separating the artwork and text into many individual layers, that I placed in receding layers of 3D depth, in a 3D program on the computer. And made sure everything outside the borders of the book is excluded, to give it the ‘portal’ effect.
Mass storage hardware breaks all the time. Sometimes it’s hardware that breaks, but sometimes it’s the software that breaks. If it’s the software (or own talent) that made the data go boom, TestDisk is a tool you should know about.
DISCLAIMER: If the data you are trying so recover is actually worth anything you might want to reserve to a professional data recovery service rather than trying to train-on-the-job.
TestDisk is powerful free data recovery software! It was primarily designed to help recover lost partitions and/or make non-booting disks bootable againwhen these symptoms are caused by faulty software: certain types of viruses or human error (such as accidentally deleting a Partition Table). Partition table recovery using TestDisk is really easy.
Fix partition table, recover deleted partition
Recover FAT32 boot sector from its backup
Rebuild FAT12/FAT16/FAT32 boot sector
Fix FAT tables
Rebuild NTFS boot sector
Recover NTFS boot sector from its backup
Fix MFT using MFT mirror
Locate ext2/ext3/ext4 Backup SuperBlock
Undelete files from FAT, exFAT, NTFS and ext2 filesystem
Copy files from deleted FAT, exFAT, NTFS and ext2/ext3/ext4 partitions.
TestDisk has features for both novices and experts. For those who know little or nothing about data recovery techniques, TestDisk can be used to collect detailed information about a non-booting drive which can then be sent to a tech for further analysis. Those more familiar with such procedures should find TestDisk a handy tool in performing onsite recovery.
And if you give up, think about writing an article of you actually digging deeper:
We consolidate location and information of wireless networks world-wide to a central database, and have user-friendly desktop and web applications that can map, query and update the database via the web.
So what’s my use-case? Apart from the obvious I will make use of this by finding out more about those fellow travelers around me. Many people probably to the same as me: Travel with a small wifi / 4g access point. Whenever this accesspoints shows up in scans the path will be traceable.
I am curious to see which access point around me is in the million-mile club yet…
Whenever we arrive at a place that we have not been before it is important to get properly connected to the internet.
Finding wifi SSIDs and typing passwords is tedious and prone to errors. There is an easier way of course!
The owner of the wireless network can generate a QR code that you can easily take a photo of and your phone will automatically prompt you to log into the wireless network without you having to type anything.
On your phone it looks like this:
To generate these QR codes that contain all information for visitors/new users to connect this simple tool / online generator can be used:
Ever wanted to create a cool QR code for your guests? But never wanted to type in your WiFi credentials into a form that submits them to a remote webserver to render the QR code? QiFi for the rescue! It will render the code in your browser, on your machine, so the WiFi stays as secure as it was before (read the code if you do not trust text on the internet :-))!
Don’t worry: your access point information is not transferred over the internet. As this is open source at the time of writing the data was held in HTML 5 local storage on the local browser only and not transferred out.
The Android tablets I am using for my kitchen scale display and for myfitnesspal data-entry are aging quite bad and apart from the near-display death of one of the tablets both are not supported and updated anymore.
Using them therefore poses an increasing risk. After one of them almost died on me I was determined to replace them both. Looking at alternatives at the lowest possible price quickly showed that I am not going to get another Android tablet.
Instead I was ready to give a chinese company a chance:
I ordered it on 24th of June and it was delivered today. All in all I’ve paid 136 Euro for the tablet and 45 Euro for the keyboard attachement.
Despite the ridiculously low price this thing is quite impressive. It’s sporting a fast-enough Intel Atom processor with 1.4 ghz and 4 Gbyte of RAM. The 64 Gb of solid-state storage where quickly upgraded by an additional 400 Gb MicroSD card for local data storage.
As of writing this it’s still installing and updating the Windows 10 to 1903 but so far I am beyond impressed.
I’ll write more about the device when I’ve had more time to use it. One word for the keyboard attachement: the keyboard is good-enough. Not great but better than for example that on the Pinebook. The touchpad is very small but works – the thing has a Touchscreen anyway.
Try to wrap your head around this: There are people out there that take the term “Maker” to new levels. People Like Sam Zeloof. He went out and created his very own integrated circuit designs and then he built them. Like the actual silicon, the die, the bonded chip, the IC. The real thing.
I am very excited to announce the details of my first integrated circuit and share the journey that this project has taken me on over the past year. I hope that my success will inspire others and help start a revolution in home chip fabrication. When I set out on this project I had no idea of what I had gotten myself into, but in the end I learned more than I ever thought I would about physics, chemistry, optics, electronics, and so many other fields. Furthermore, my efforts have only been matched with the most positive feedback and support from the world; I owe a sincere thanks to everyone who has helped me, given me advice, and inspired me on this project. Especially my amazing parents, who not only support and encourage me in any way they can but also give me a space to work in and put up with the electricity costs… Thank you!
Imagine you’ve got this ancient piece of technology in front of you. You clearly understand how the hardware works and you are even able to emulate the hardware on your modern-world computer.
Unfortunately hardware is only one half of the story. Software is the other half. And software at this time of the past was burned into chips which do not easily give their secret software away.
But let’s start with the hardware:
The IBM 5100 Portable Computer is a portable computer (one of the first) introduced in September 1975, six years before the IBM Personal Computer. It was the evolution of a prototype called the SCAMP (Special Computer APL Machine Portable) that was developed at the IBM Palo Alto Scientific Center in 1973. In January 1978, IBM announced the IBM 5110, its larger cousin, and in February 1980 IBM announced the IBM 5120. The 5100 was withdrawn in March 1982.
When the IBM PC was introduced in 1981, it was originally designated as the IBM 5150, putting it in the “5100” series, though its architecture was not directly descended from the IBM 5100.
And now on to the software:
The IBM 5100 portable computer came with some of its built-in programs stored in a read-only memory called the “non-executable ROS”. (ROS = “read-only storage”.) In contrast with the “executable ROS”, which supplies instructions to the 5100’s processor directly, the non-executable ROS is accessed using sequential I/O operations, a bit like a tape.
Most notably, the non-executable ROS holds the interactive interpreters for the APL and BASIC programming languages. These are not “native” 5100 programs but were expressed instead in System/370 mainframe and System/3 minicomputer machine code respectively. The 5100 runs emulator programs for those computers in order to host the interpreters, so perhaps it’s just as well that the non-executable ROS is non-executable.
So this write-up is all about how the bits where pushed to the screen and recorded as pictures of the said screen. The characters in these pictures then where analyzed and with the help of machine learning the data could be successfully extracted. It is mind-boggling. And it is all on Github.