Finally, Tame The Si5351!

The Si5351 is an extremely useful device, containing multiple clock generators with many versatile programming options that go well beyond its original purpose of providing a clock for digital circuitry. It has in particular found a spot in RF projects, where it provides a cheap and effective stand-in for a variable frequency oscillator in everything from receivers to VNAs. It’s fair to say that programming the Si5351 isn’t the easiest of tasks though, and joining the various attempts to make this simpler is [MR-DOS], who has created an Si5351 library for the STM32 range of ARM Cortex M processors. Fortunately for those afflicted by the semiconductor shortage there’s the advice that porting it to other architectures should only require the relatively manageable task of modifying the i2c function for the new hardware.

Instead of being a full abstraction layer for frequency generation, this library provides functions to give access to the nuts-and-bolts of the chip such as PLL dividers. Thus there’s a need to understand the workings of a PLL and calculate its parameters, while in return much more flexibility over the chip’s operation can be had. We like this approach even though it requires a little more work from the developer.

Over the years this device has attracted a variety of libraries, this isn’t the first we’ve featured.

Header image: Adafruit Industries (CC BY-NC-SA 2.0)

A Rotary Phone As A Computer Peripheral

It’s an age-old conundrum for anyone working with retro hardware: preserve its original condition or not? The answer depends so often on a complex mix of how rare, obsolete or unusable the device is in its original form , and what the intended use for the device will be. For [Typhon Mind] who needed a novelty method of recording best wishes at a wedding through an old dial phone there was no need for it to be entirely original, so the solution was to turn it into a USB device for a host computer.

Out went the original circuitry, and in came a USB hub, a USB audio interface, and an Arduino. The original earpiece would suffice, but the microphone was replaced with a more modern one. The Arduino will register the cradle switch, and also power a set of LED addressable lights under the unit.

The result is a phone that retains all its looks, but has a new life as a PC peripheral. We’d venture to suggest that also using the Arduino to read the dial and produce DTMF tones might make it a valid peripheral for a VOIP application and complete the transformation, but that’s something that could be done at a later date. Maybe it could even be given a GSM makeover.

Bring A Minitel Terminal Back To Life WIth An ESP32

Most of us who are old enough are likely to have had our first experience of an online service some time in the 1990s, either through the likes of Compuserve or via an ISP. For our French readers the online experience will have come much earlier, as a forward-thinking telecommunications environment led to every household in the country receiving a viewdata terminal. The Minitel system as it was called was a runaway success, and was only finally turned off as late as 2012. Many of the terminals survive to make a great basis for projects, and it’s one of these that [Louis H] has taken and enhanced with an ESP32.

One of the special things about this project is that unlike so many other Minitel conversions it doesn’t involve tearing into the terminal itself. Instead the PCB plugs into the socket on the back of the unit and emulates the line for the terminal to talk to. It can then be used as an SSH terminal over WiFi, or as a serial terminal for the ESP32 itself for example running a MicroPython firmware. If you can handle the French AZERTY keyboard there is no easier way to drag a viewdata terminal into the 2020s, as you can see in the video below the break.

Chez Hackaday, we love these nostalgic gems from the 1980s. Indeed we like this classic French public network so much that we’ve featured it quite a few times. Here for example is a similar project using an Arduino. Continue reading “Bring A Minitel Terminal Back To Life WIth An ESP32”

You Can’t Upgrade Soldered-On Laptop RAM? Think Again

Upgrading the memory in a computer is usually a straightforward case of swapping out a few DIMMs or SODIMMs, with the most complex task being to identify the correct type of memory from the many available. But sometimes a laptop manufacturer can be particularly annoying, and restrict upgradability by soldering the RAM chips directly to the board. Upgrading memory should then be impossible, but this reckons without the skills of [Greg Davill], who worked through the process on his Dell XPS13.

The write-up is a fascinating primer on how DRAM identification works, which for removable DIMMs is handled by an onboard FLASH chip containing the details of the chips on board. A soldered-on laptop has none of these, so instead it employs a series of resistors whose combination tells the BIOS what memory to expect. Some research revealed their configuration, at which point the correct chips were sourced. Surprisingly it’s not as easy as one might expect to buy small quantities of some RAM chips, but he was eventually able to find some via AliExpress. An aside is how he checked the chips he received for fakes, including the useful tip of hiring a dentist to take an x-ray.

The final step is the non-trivial task of reballing and reworking the new BGAs onto the board, before testing the laptop and finding the process to be a success. We’ll leave you with his final words though: “But next time I think I’ll just buy the 16GB variant upfront.“.

We’ve seen quite a lot of [Greg]’s work here at Hackaday, one of his most recent was this amazing LED D20.

A Trackball So Good You Can’t Buy It

The projects we feature on Hackaday are built to all standards, and we’d have to admit that things have left our own benches as bundles of wire and tape. Sometimes we see projects built to such a high standard that we’re shocked that they aren’t a high-end manufactured product, such as [jfedor2]’s two-ball trackball project. It combines a pair of billiard balls and a couple of buttons with a beautifully-designed 3D-printed case that looks for all the world as though it came from a premium peripheral brand.

Inside are a pair of PMW3360 optical sensors on PCBs mounted with a view into the billiard ball sockets, and for which the brains come courtesy of an RP2040 microcontroller. There are five PCBs in all, each having a set of purpose-built stand-offs to hold it. The result appears to be about as good a trackball as you’d hope to buy, except of course that you can’t. All the files to make your own are in the GitHub repository though, so all is not lost.

Over the years we’ve brought you a variety of trackball designs, including at least one other build using a billiard ball.

It’s Doom, This Time On A Bluetooth LE Dongle

By now most readers should be used to the phenomenon of taking almost any microcontroller and coaxing it to run a port of the 1990s grand-daddy of all first-person shooters, id Software’s Doom. It’s been done on a wide array of devices, sometimes only having enough power for a demo mode but more often able to offer the full experience. Latest to the slipgate in this festival of pixelated gore is [Nicola Wrachien], who’s achieved the feat using an nRF52840-based USB Bluetooth LE dongle.

Full details can be found on his website, where the process of initial development using an Adafruit CLUE board is detailed. A 16MB FLASH chip is used for WAD storage, and an SPI colour display takes us straight to that cursed base on Phobos. The target board lacks enough I/O brought out for connection to screen and FLASH, so some trickery with 7400 logic is required to free up enough for the task. Controls are implemented via a wireless gamepad using an nRFS1822 board, complete with streamed audio to a PWM output.

The result can be seen in the video below the break, which shows a very playable game of both Doom and Doom 2 that would not have disgraced many machines of the era. This was prototyped on an Adafruit Clue board, and that could be the handheld console you’ve been looking for!

Continue reading “It’s Doom, This Time On A Bluetooth LE Dongle”

Video Gaming Like It’s 1983: New Game Cartridges From Atari

If you remember anything from 1983, it’s likely to be some of the year’s popular culture highlights, maybe Return of the Jedi, or Michael Jackson’s Thriller. For anyone connected with the video gaming industry though, it’s likely that year will stick in the mind for a completely different reason, as the year of the infamous Great Video Games Crash. Overcapacity in the console market coupled with a slew of low quality titles caused sales to crash and a number of companies to go out of business, and the console gaming world would only recover later in the decade with the arrival of the Japanese 8-bit consoles from Nintendo and Sega. You might expect Atari to shy away from such a painful period of their history, but instead they are embracing it as part of their 50th anniversary and launching three never-released titles on cartridges for their 8-bit 2600 console.

Game footage from Aquaventure.
Game footage from Aquaventure.

The three games, Yars’ Return, Aquaventure, and Saboteur, are all unreleased titles from back in the day that never saw publication because of the crash, and are being released as limited edition specials through AtariXP, a new venture that the company says will offer “previously unreleased titles from Atari’s expansive library, rare-and-hard-to-find Atari IP physical media, and improved versions of classic games“. It’s fairly obviously an exercise in satisfying the collector’s market rather than one of video game publishing, but it will be interesting to see what emerges. In particular we hope someone will tear down one of these cartridges; will they find a set of old-school EPROMs inside or an EPROM emulator sporting a microcontroller and other 2020s trickery?

This is not of course the first time we’ve reported on collectable 2600 cartridges, but these ones haven’t spent 30 years in a landfill site.

Header image: Evan-Amos, Public domain.