PCIe For Hackers: The Diffpair Prelude

PCIe, also known as PCI-Express, is a highly powerful interface. So let’s see what it takes to hack on something that powerful. PCIe is be a bit intimidating at first, however it is reasonably simple to start building PCIe stuff, and the interface is quite resilient for hobbyist-level technology. There will come a time when we want to use a PCIe chip in our designs, or perhaps, make use of the PCIe connection available on a certain Compute Module, and it’s good to make sure that we’re ready for that.

PCIe is everywhere now. Every modern computer has a bunch of PCIe devices performing crucial functions, and even iPhones use PCIe internally to connect the CPU with the flash and WiFi chips. You can get all kinds of PCIe devices: Ethernet controllers, high-throughput WiFi cards, graphics, and all the cheap NVMe drives that gladly provide you with heaps of storage when connected over PCIe. If you’re hacking on a laptop or a single-board computer and you’d like to add a PCIe device, you can get some PCIe from one of the PCIe-carrying sockets, or just tap into an existing PCIe link if there’s no socket to connect to. It’s been two decades since we’ve started getting PCIe devices – now, PCIe is on its 5.0 revision, and it’s clear that it’s here to stay.

Continue reading “PCIe For Hackers: The Diffpair Prelude”

A Thoroughly Modern Serial Terminal

The humble desktop serial terminal may have long disappeared from the world of corporate IT, but there are still plenty of moments when professionals and enthusiasts alike need to hook up to a serial port. Many of us use a serial port on our laptops or other mobile devices, but [Neil Crawforth] has gone one better than that with the VT2040. It’s an old-style serial terminal in a super-handy portable format, and as one might guess from the name, it has an RP2040 microcontroller at its heart.

Attached to the chip is a rather nice keyboard, and an ILI9488 480×320 LCD display. The software is modular, providing a handy set of re-usable libraries for the different functions including a PIO-based serial port. His main application seems to be talking to an ESP8266, but we’re guessing with a MAX232 or other level shifter chip it could drive a more traditional port. Everything can be found in the project’s GitHub repository, allowing anyone to join the fun.

As long-time readers will know, we’ve been partial to a few serial terminals in the past. Particularly beloved is this extremely retro model with vintage dot matrix LEDs.

Floppy-8 Is A Tiny PC In A Floppy Drive

At first sight, Floppy-8 is simply a LattePanda based PC built into the shell of a external vintage floppy drive. Indeed, it’s a very nicely executed LattePanda PC in a floppy, and we’re impressed by it. What turns it from a nifty case mod into something a bit special though, is the way creator [Abraham Haskins] has used floppy-like cartridges in the original floppy slot, as a means of loading software.

The cartridges started out as PCBs in the shape of a floppy with an SD socket on their bottom, and progressed to USB drives on 3D printed cartridges and finally and simplest of all, the same 3D printed cartridges with micro SD cards embedded in their leading edges. All this was necessary to get them thin enough to fit into the existing disk slot — if dimensions weren’t a concern, you could enclose various USB devices into printed cartridges. A script on the computer looks for new card insertion, and runs the appropriate autostart.sh script on the SD card if it finds one. If you don’t need the “disks” to fit into an existing slot, you could print them larger and embed

Beyond the cartridges, the PC itself is assembled on a 3D printed frame inside the case. It’s controlled via Bluetooth, with a pair of knock-off NES controllers for games and an Amazon Fire remote for media. We particularly like the idea of weighting the controllers with ball bearings to give them a little heft.

The LattePanda gives the Raspberry Pi a run for its money in these applications. We particularly liked this portable Macintosh.

Two people lounge over a wooden tabletop to lean on a large black laptop. It has a green leaf on its 43" LCD desktop and RGB lighting around its edge is glowing a slightly deeper shade of green.

Supersized Laptop Laughs In The Face Of Portability

Sometimes a project needs to go big, and [Evan and Katelyn] threw portability to the wind to build the “world’s biggest” laptop.

Stretching the believability of “bigger is better,” this laptop features a 43″ screen, an enormous un-ergonomic keyboard, and a trackpad that might be bigger than your hand. Not to be outdone by other gaming laptops, it also features RGB lighting and a logo that really pops with neon resin.

The pair started the build with an aluminum extrusion frame joined by hinges. Plywood forms the top lid and bottom of the device, and the interior was covered with a mix of vinyl and ABS to keep everything tidy. A nice detail is the windows cut in the area above the keyboard to keep an eye on the charge of the two battery packs powering the laptop. Weighing more than 100 pounds, we suspect that this won’t be the next revolution in computing.

If you need more supersized gadgets, maybe try out the world’s biggest working keyboard or this giant Xbox Series X?

How To Build Jenny’s Budget Mixing Desk

Jenny did an Ask Hackaday article earlier this month, all about the quest for a cheap computer-based audio mixer. The first attempt didn’t go so well, with a problem that many of us are familiar with: Linux applications really doesn’t like using multiple audio devices at the same time. Jenny ran into this issue, and didn’t come across a way to merge the soundcards in a single application.

I’ve fought this problem for a while, probably 10 years now. My first collision with this was an attempt to record a piano with three mics, using a couple different USB pre-amps. And of course, just like Jenny, I was quickly frustrated by the problem that my recording software would only see one interface at a time. The easy solution is to buy an interface with more channels. The Tascam US-4x4HR is a great four channel input/output audio interface, and the Behringer U-PHORIA line goes all the way up to eight mic pre-amps, expandable to 16 with a second DAC that can send audio over ADAT. But those are semi-pro interfaces, with price tags to match.

But what about Jenny’s idea, of cobbling multiple super cheap interfaces together? Well yes, that’s possible too. I’ll show you how, but first, let’s talk about how we’re going to control this software mixer monster. Yes, you can just use a mouse or keyboard, but the challenge was to build a mixing desk, and to me, that means physical faders and mute buttons. Now, there are pre-built solutions, with the Behringer X-touch being a popular solution. But again, we’re way above the price-point Jenny set for this problem. So, let’s do what we do best here at Hackaday, and build our own. Continue reading “How To Build Jenny’s Budget Mixing Desk”

Old 3D CAD Mouse Gets New Lease Of Life

[Jacek Fedorynski] had an old Magellan/SpaceMouse 3D mouse with a serial interface which made it impossible for him to use with modern hardware and software. The problem he faced was two pronged – the absence of serial interfaces in the hardware and the lack of appropriate drivers for the operating system. So he built a low cost, simple adapter to use his RS-232 Magellan/SpaceMouse with modern software.

The hardware required to build the adapter was minimal. A Raspberry Pi Pico, a MAX3238 based RS-232 adapter, a null modem adapter and a DB9 gender changer. Of course, a combination null modem – gender changer would have made things even simpler. Four of the GPIO pins from the Pico are mapped to the serial RX, TX, RTS and CTS pins.

On the software side, the code emulates a 3DConnexion SpaceMouse Compact, so it can be used with software like Fusion 360, 3ds Max, SolidWorks, Inventor, Maya and many others. On the host computer, only the standard 3DxWare driver package is needed. On the host computer, the old Magellan/SpaceMouse 3D will appear like a modern SpaceMouse Compact connected over USB. The only downside to this is that the SpaceMouse Compact has just two programmable buttons, so only two of the many buttons on the old Magellan mouse can be mapped.

Flashing the code to the Pico is also straightforward using the BOOTSEL mode. Hold down the BOOTSEL button when plugging in the Pico and it appears as a drive onto which you can drag a new UF2 file. Just drag-n-drop [Jacek]’s magellan.uf2 firmware and you’re done.

If you’d rather build your own, modern 3D mouse, check out the DIY Cad Mouse You Can Actually Build.

Surfing The Web Like It’s 1978 — Carbonyl

[Fathy] gets a kick out of doing odd things with Chromium, and Carbonyl is a clever byproduct of that hobby. In this case, it’s what you get when you connect chrome’s renderer to an SVG output module and then convert that SVG to colored characters on a terminal. See, html2svg is an earlier project, taking Chromium’s Skia engine and plugging it into an SVG back-end. And once you have SVG, why not render it to the terminal?


And the results are actually pretty impressive. Imagery is rendered using Unicode 2584, a half-block character. The background and foreground color can be set per character, giving us two controllable pixels per character. Text is handled a bit differently, rendering using the normal text fonts, making for readable pages.

The source is very much a work in progress, but there are some neat ideas already coalescing around the project, like using sixels for better rendering. There’s already decent mouse support and audio output, making for an impressive terminal experience. This might be a project to keep an eye on.