I needed some cheap little vregs recently and had run out of and/or lost all of my useful-value 780x linear parts, so I decided to look at what people in this century use.
I found some little buck boards roughly the size of a TO-220 package that looked exciting. These particular ones are QSKJ Mini DC-DC Buck Step Down Module model “QS-1205CME-3A”, Vendor page here, mine were 5pcs/$9 from Amazon.
Upon analysis they have serious issues with regulating under load, so the hunt for something decent continues, but the form-factor and advertised feature set are really compelling.
Pros:
High-efficiency high-frequency synchronous buck instead of a linear heater^H^H regulator.
Solder-jumpers for 1.8,2.5,3.3,5,9,12V or a default (fiddly, tiny) adjustment pot output so you only have to stock one device – one easy-to-cut trace to disable adjustable mode.
Tolerates 4.5-24V input as long as out < in or so.
Good stability to input voltage variation.
~0.25V drop-out.
Does appear to have a cutoff for over-current.
No perceptible ripple under various load conditions.
Cons:
Voltage regulation manages maybe 600mA at 5V before droop becomes unacceptable (<4.8v).
…and that makes it basically useless for most applications. Test data below the fold.
Maybe it could be resolved with appropriate external capacitors and/or offsetting the adjustable to regulate right at a known load or something, but not being drop-in really reduces their charm.
Anyone know of a similar offering that doesn’t suck at output regulation? (Rel: Anyone know if any of the low-end electronic loads are worthwhile? I’m not looking to spend real-lab-instrument money, but it’s come up often enough lately that I want to be able to dissipate a couple 10s of Watts through a at least stepwise-controllable resistive load).
Article note: Michael Sweet (who is responsible for almost all CUPS commits) left Apple and has a fork that is being actively maintained.
I wonder if Apple has a plan here. Are they just ignoring the license and keeping their patches in-house? Have they decided printing is not a priority and are just parasiting a hand-me-down for "good enough"?
After only one public Git commit this year, penguinstas think: Fork it, we don't need Cupertino
The official public repository for CUPS, an Apple open-source project widely used for printing on Linux, is all-but dormant since the lead developer left Apple at the end of 2019.…
Google is, once again, changing up its messaging app strategy. The company plans to make Chat, its Slack-like app, free for everyone in 2021, when it will push people currently using Hangouts to use Chat instead. If you’re having trouble keeping trac...
Article note: Yes,but also the publicly funded but central method is attractive from the current state, but probably not actually a good plan.
Doing it the "publicly funded but central" way will make the "small government low taxes" folks angry, cause moderation problems that make Facebook and NextDoor look easy, and... hoo boy are the people who have recently discovered that the platforms they used to organize and advance their interests in the past can _also_ be used for _causes they find reprehensible_ going to be mad as this undermines their efforts to pull up ladders.
Article note: I did not know that about ARM (before 8) parts.
Clever encoding, useful (and used) for PUSH/POP, and fast copy routines, and a little restrictive and inconvenient to implement.
Google and Intel are warning of a high-severity Bluetooth flaw in all but the most recent version of the Linux Kernel. While a Google researcher said the bug allows seamless code execution by attackers within Bluetooth range, Intel is characterizing the flaw as providing an escalation of privileges or the disclosure of information.
The flaw resides in BlueZ, the software stack that by default implements all Bluetooth core protocols and layers for Linux. Besides Linux laptops, it's used in many consumer or industrial Internet-of-things devices. It works with Linux versions 2.4.6 and later.
In search of details
So far, little is known about BleedingTooth, the name given by Google engineer Andy Nguyen, who said that a blog post will be published “soon.” A Twitter thread and a YouTube video provide the most detail and give the impression that the bug provides a reliable way for nearby attackers to execute malicious code of their choice on vulnerable Linux devices that use BlueZ for Bluetooth.
Article note: I get a decent amount of sun, eat a varied diet, and am generally skeptical of dietary supplements ... I've been popping a couple 1k IU D3 tablets a week lately based on both the COVID-19 and general "Everyone no near the equator" Vitamin D news of late.
Article note: Aw, man, I was hoping someone did a teardown.
I've been super curious what the switch mechanism (8 switches? an analog stick?) in those things is for years, but not $300 curious.
I can’t remember how exactly I came across the OrbiTouch keyboard, but it’s been on my list to clack about for a long time. Launched in 2003, the OrbiTouch is a keyboard and mouse in one. It’s designed for people who can’t keyboard regularly, or simply want a different kind of experience.
The OrbiTouch was conceived of by a PhD student who started to experience carpal tunnel while writing papers. He spent fifteen years developing the OrbiTouch and found that it could assist many people who have various upper body deficiencies. So, how does it work?
It’s Like Playing Air Hockey with Both Hands
To use this keyboard, you put both hands on the sliders and move them around. They are identical eight-way joysticks or D-pads, essentially. The grips sort of resemble a mouse and have what looks like a special resting place for your pinky.
One slider points to groups of letters, numbers, and special characters, and the other chooses a color from a special OrbiTouch rainbow. Pink includes things like parentheses and their cousins along with tilde, colon and semi-colon. Black is for the modifiers like Tab, Alt, Ctrl, Shift, and Backspace. These special characters and modifiers aren’t shown on the hieroglyphs slider, you just have to keep the guide handy until you memorize the placement of everything around the circle.
You’re gonna need a decent amount of desk space for this. Image via OrbiTouch
The alphabet is divided up into groups of five letters which are color-coded in rainbow order that starts with orange, because red is reserved for the F keys. So for instance, A is orange, B is yellow, C is green, D is blue, E is purple, then it starts back over with F at orange. If you wanted to type cab, for instance, you would start by moving the hieroglyph slider to the first alphabet group and the color slider to green.
Slide Along the Rainbow
The interesting thing about this keyboard and this particular word is that all the letters for cab are in the first group. The keyboard will let you keep one of the sliders in place if you have repeated colors or letter groups, so you can keep the alpha slider in place and just move the rainbow slider around from green to orange to yellow to spell cab. Let’s watch it type ‘Hackaday’ over and over:
A selection from the slide guide. Image via OrbiTouch
Every letter, number, and special character has an equivalent directional pair that may or may not be easy to memorize. According to the FAQ, the maximum output you can expect from this thing is 30-40WPM. Although it is a combination keyboard and mouse, if you play any games that are more serious than say, Minesweeper,
forget about it. You’ll have to keep switching between keyboard and mouse mode, and it’s a whole thing, and you’re gonna die really quickly.
I think the color code is a great idea, but if you’re colorblind, it’s likely not going to be the keyboard for you. Also, you would have to have the use of both hands and a pretty good amount of coordination to be able to drive this keyboard/mouse hybrid creature. On the plus side, every gesture requires equal force, which is fairly low.
conclusion
Apparently this keyboard rates highly with autistic people because of the alphabetically rainbow-tastic way that the inputs are laid out. Those aesthetic choices are definitely a high point in my book. I think it’s neat that it’s so totally different from any other keyboard. It looks fun to try, at least for little while. Though I can’t imagine typing an entire Hackaday article on one, it looks way more fun to learn than Dvorak. I might buy one someday, but the OrbiTouch is a touch on the expensive side at $399, or you can pick them up used for around $200. They were actually sold out of both the black-and-white versions on the OrbiTouch website at the time of this writing, but there are a few out there on the electronic bay.
So is this keyboard really assistive technology? It kind of depends on your level of functioning. If typing hurts, but you still need to do it, this could be your saving grace. All things considered, I would think that all the joystick motion would aggravate wrist issues or even cause them, but since I haven’t tried actually tried one out, I can’t say for sure. Have any of you tried one?
Article note: It was such a weird rumor, the NT kernel is _fucking great_ in a lot of ways. The Windows userland has never been anything particularly special, and we're getting WSL so we can have a UNIX userland hosted (...much like the way Domain/OS could virtually host various UNIXes).
Article note: I guess Intel bought Altera so AMD feels the need to own a top-tier FPGA vendor as well?
Xilinx did make a bunch of HyperTransport-compatible FPGA modules back when that was a thing, so perhaps they have an established working relationship they plan to exploit?
Moreover, under existing conditions, private capitalists inevitably control, directly or indirectly, the main sources of information (press, radio, education). It is thus extremely difficult, and indeed in most cases quite impossible, for the individual citizen to come to objective conclusions and to make intelligent use of his political rights.
