Author: Jenny List

2977 Articles

A Journey Into Unexpected Serial Ports

August 24, 2024 by 17 Comments

Through all the generations of computing devices from the era of the teleprinter to the present day, there’s one interface that’s remained universal. Even though its usefulness as an everyday port has decreased in the face of much faster competition, it’s fair to say that everything has a serial port on board somewhere. Even with that ubiquity though, there’s still some scope for variation.

Older ports and those that are still exposed via a D socket are in most case the so-called RS-232, a higher voltage port, while your microcontroller debug port will be so-called TTL (transistor-transistor logic), operating at logic level. That’s not quite always the case though, as [Terin Stock] found out with an older Garmin GPS unit.

Pleasingly for a three decade old device, given a fresh set of batteries it worked. The time was wrong, but after some fiddling and a Windows 98 machine spun up it applied a Garmin update from 1999 that fixed it. When hooked up to a Flipper Zero though, and after a mild panic about voltage levels, the serial port appeared to deliver garbage. There followed some investigation, with an interesting conclusion that TTL serial is usually the inverse of RS-232 serial, The Garmin had the RS-232 polarity with TTL levels, allowing it to work with many PC serial ports. A quick application of an inverter fixed the problem, and now Garmin and Flipper talk happily.

Tiny ’90s Laptop Gets Modern Power

August 21, 2024 by 19 Comments

The laptop to have here in the 2020s varies depending on who you ask, perhaps a Framework, or maybe a ThinkPad. Back in the 1990s the answer might have included a now-forgotten contender, because in that decade Toshiba made a range of legendarily tough chunky grey machines. Of these the smallest was the Libretto, a paperback book sized clamshell design which was an object of desire. It’s one of these that [Robert’s Retro] has upgraded to use USB-C power instead of the original power brick.

The full video is below the break, and while it first deals with replacing a defective screen, the power part starts just before 22 minutes in. As you’d expect it involves a USP-C PD trigger board, this time at 15 volts. It’s mounted in a small 3D printed adapter to fill the space of the original jack, and requires a tiny notch be removed from the corner of its PCB to fit round the motherboard. The rest of the video deals with reassembling the machine and tending to mishaps with the ageing plastic, but the result is a Libretto with a modern charging port.

Naturally a machine with a Pentium CPU and 32 megabytes of RAM is in of limited use in modern terms, but these Librettos remain very well-designed tiny PCs to this day. It’s great to see them still being modified and upgraded, even if perhaps there’s a limit to how far you can push their computing power. We’ve encountered the Libretto before a few times, such as when one was used to retrieve data from an old Flash card.

Continue reading “Tiny ’90s Laptop Gets Modern Power” →

WOW! It Wasn’t Aliens After All!

August 20, 2024 by 21 Comments

There may not be many radio astronomy printouts that have achieved universal fame, but the one from Ohio State University’s Big Ear telescope upon which astronomer [Jerry R. Ehman] wrote “WOW!” is definitely one of them. It showed an intense one-off burst that defied attempts to find others like it, prompting those who want to believe to speculate that it might have been the product of an extraterrestrial civilization. Sadly for them the Planetary Habitability Laboratory at the University of Puerto Rico at Arecibo has provided an explanation by examining historical data from the Arecibo telescope.

The radio signal in question lay on the hydrogen line frequency at 1420 MHz, and by looking at weaker emissions from cold hydrogen clouds they suggest that the WOW! signal may have come from a very unusual stimulation of one of these clouds. A magnetar is a type of neutron star which can create an intense magnetic field, and their suggestion is that Big Ear was in the lucky position of being in the right place at the right time to see one of these through a hydrogen cloud. The field would excite the hydrogen atoms to maser-like emission of radiation, leading to the unexpected blip on that printout.

There’s a question as to whether speculation about aliens is helpful to the cause of science, but in answer to that we’d like to remind readers that we wouldn’t be talking about magnetars now without it, and that the WOW! signal was in fact part of an early SETI experiment. Better keep on searching then!

Meanwhile readers with long memories will recollect us looking at the WOW! signal before.

Close-Up On The RP2350 HSTX Peripheral

August 20, 2024 by 24 Comments

The new Raspberry Pi Pico 2 with its RP2350 microcontroller has only been with us for a short time, and thus its capabilities are still being tested. One of the new peripherals is HSTX, for which the description “High speed serial port” does not adequately describe how far it is from the humble UART which the name might suggest. CNX Software have taken a look at its capabilities, and it’s worth a read.

With a 150 MHz clock and 8 available pins, it’s a serial output with a combined bandwidth of 2400 Mbps, which immediately leaves all manner of potential for streamed outputs. On the RP2040 for example a DVI output was made using the PIO peripherals, while here the example code shows how to use these pins instead. We’re guessing it will be exploited for all manner of pseudo-analogue awesomeness in the manner we’re used to with the I2S peripherals on the EP32. Of course, there’s no corresponding input, but that still leaves plenty of potential.

Have a quick read of our launch coverage of the RP2350, and the Pico 2 board it’s part of.

A USA Feature For A Europe-Market Sony Receiver

August 16, 2024 by 23 Comments

A feature of many modern network-connected entertainment devices is that they will play streamed music while on standby mode. This so-called “network standby”is very useful if you fancy some gentle music but don’t want the Christmas lights or the TV. It was a feature [Caramelfur] missed on their Sony AV receiver, something especially annoying because it’s present on the US-market equivalent of their European model. Some gentle hackery ensued, and now the rece3iver follows its American cousin.

A first examination of the firmware found the two downloads to be identical, so whatever differences had to be in some form of configuration. Investigating what it exposed to the network led to a web server with device configuration parameters. Some probing behind the scenes and a bit of lucky guesswork identified the endpoint to turn on network standby, and there it was, the same as the US market model. Should you need it, the tooling is in a GitHub repository.

This isn’t the first time we’ve seen identical hardware being shipped with different firmwares in Europe from that in the USA, perhaps our most egregious example was a Motorola phone with a much earlier Android version for Europeans. We don’t understand why manufacturers do it, in particular with such an innocuous feature as network standby. If you have a Sony receiver you can now fix it, but you shouldn’t have to.

RJ45, Devcore, CC0.

Make A Catch With A 3D Printed Rod

August 15, 2024 by 7 Comments

When we think of fishing rods, the image brought to mind is one of a tweed-clad fisherman in his waders in a wild salmon stream, his line whipping about as it guides the fly over the surface of the water. Angling is a pursuit with a heritage, and having a lengthy rod seems an essential for its enjoyment. But perhaps your tackle needn’t be such an important factor, and in that spirit here’s [3dcreation] with a tiny but fully functional 3D printed fishing rod.

If you’ve ever seen a fisherman working through a hole in the ice, you may have some idea of the type of rod in question, it’s a stubby affair half handle and half rod, with a rudimentary reel in the middle. In the pictures it’s loaded up with line, weight ready to go, so we can see how it’s supposed to work. We’re not anglers here though, so the question of whether it would indeed work is one for your imagination.

Perhaps surprisingly, few anglers find their way onto these pages. One of the few that has, used a drone.

Help The LEGO Camera Become A Reality

August 15, 2024 by 9 Comments

Some time over a year ago, we told you about a camera. Not just any camera, but a fully-functional 35mm film camera made entirely of LEGO, and with a pleasingly retro design into the bargain. It’s the work of [Zung92], and it can be found on the LEGO Ideas website.

You might now be asking why we’re talking about it again so soon, and the answer comes in its approaching the deadline for being considered by LEGO for a set. Projects on the Ideas website move forward when they achieve 10,000 supporters, and this one’s just shy of 8,000 with a month to go. We like this project and we think it deserves to see the light of day, and perhaps with your help it can.

When we covered this project last time we lamented the lack of technical detail, so we’re pleased to see a glimpse inside it as part of a manual uploaded to the updates page. We’d be the first to remark that with its LEGO part plastic lens and quarter-frame pictures it won’t be the best camera ever, but that’s hardly the point. Cameras like this one are a challenge, and it seems as though this one is perfect for the competition with a difference.