A gray 3d-printed box with RV-bridge embossed on it, and a connector-terminated bundle of wires coming out of it.

RV-Bridge Takes HomeKit To The Open Road

March 9, 2023 by Arya Voronova 20 Comments

In the world of proprietary protocol darkness, it’s comforting to see that the RV realm (Recreational Vehicle, also known as a motorhome) has mostly settled on RV-C, an open protocol that lets various devices and systems inside an RV talk to each other over CAN. The undeniable openness of RV-C is surprising, but we haven’t seen many hobbyists tinker with it — yet.

Now, [Randy Ubillos] sets an example — his gift to us is an ESP32 firmware called RV-Bridge and it lets you control your RV’s RV-C network from HomeKit. After all, your motorhome could benefit from home automation, too!

The RV-C network in [Randy]’s family RV already had a factory-provided front-end and an iOS app, but naturally, it had a limited set of features. Having looked around online he found that both RV-C and HomeKit had open libraries for them, and set out to join these worlds together.

Now he’s released the first revision of RV-Bridge, fully-featured enough for comfortable day-to-day use, and with a setup guide for those who want to try it out! When it comes to hardware, you’ll want an ESP32 board with CAN support — [Randy] has found a perfect board for sale, and made it even more fitting by designing a 3D printed case for RV use; as usual, files are on GitHub!

Making your stock RV more comfy through hacker methods is exactly what we expect to grace our tips line! The kinds of RV projects we’ve seen so far, are also outstandingly cool, yet of different kind – things like building your own RVs out of something not meant to be an RV, whether it’s an abandoned airliner, a school bus, or a jet engine! Oh, and if your hackerspace owns a RV, you can always convert it to something else, be it a mobile hackerspace or a spaceship simulator.

Laptop Motherboard? Let’s Boot And Tinker

March 7, 2023 by Arya Voronova 12 Comments

Last time, I’ve shared my experience on why you might want to consider a laptop motherboard for a project of yours, and noted some things you might want to keep in mind if buying one for a project. Now, let’s go through the practical considerations!

Making It Boot

Usually, when you plug some RAM and a charger into a board, then press the power button, your board should boot up and eventually show the BIOS on the screen. However, there will be some caveats – it’s very firmware-dependent. Let me walk you through some confusing situations you might encounter.

If the board was unpowered for a while, first boot might take longer – or it might power on immediately after a charger has been plugged in, and then, possibly, power off. A bit of erratic behaviour is okay, since boards might need to do memory training, or recover after having lost some CMOS settings. Speaking of those, some boards will not boot without a CMOS battery attached, and some will go through the usual ‘settings lost’ sequence. Sometimes, the battery will be on a daughterboard, other times, especially with new boards, there will be no CR2032 in sight and the board will rely on the main battery to provide CMOS settings saving functions – in such case, if you don’t use the battery, expect the first boot to take longer, at least. Overall, however, pressing the power switch will cause the board to boot. Continue reading “Laptop Motherboard? Let’s Boot And Tinker” →

A Pi Pico plugged into a breadboard, with jumpre wires going away from its pins to an SPI flashing clip, that's in turn clipped onto an SPI flash chip on a BeagleBone board

Programming SPI Flash Chips? Use Your Pico!

March 6, 2023 by Arya Voronova 10 Comments

At this point, a Pi Pico is equivalent to a bag full of programmers and debugging accessories. For instance, when you want to program an SPI flash chip, do you use one of those wonky CH341 dongles, or perhaps, even a full-on Raspberry Pi with a Linux OS? If so, it might be time to set those two aside – any RP2040 board can do this now. This is thanks to work of [stacksmashing] who implemented serprog protocol for the RP2040, letting us use a Pi Pico with stock flashrom for all our SPI flash chip needs.

After flashing the code to your RP2040 board, all you need to do is to wire your flash chip to the right pins, and then use the serprog programmer type in your flashrom commandline – instructions are available on GitHub along with the code, as you’d expect. Don’t feel like installing flashrom, or perhaps you happen to run Windows and need a flasher in a pinch? [stacksmashing] has a WebSerial-based SPI flasher tool for you, too, and shows it off with a fancy all-the-pinouts board of his own making.

This kind of tool is indispensable – you don’t need to mod one of these CH341 programmers to fix the bonkers 5 V default IO, or keep an entire Linux computer handy when you likely already have one at your fingertips. All in all, yay for one more RP2040 trick up our sleeve – this SPI flashing helper joins an assortment of applets for SWD, JTAG, UART, I2C and CAN, and in a pinch, your Pi Pico will also work as a digital and analog logic analyzer or an FPGA playground.

Showing a RAM chip being removed from a Pi 4 board, hot air gun in the shot. Area around the chip is covered with kapton tape.

Upgrade RAM On Your Pi 4, The Fun Way

March 5, 2023 by Arya Voronova 17 Comments

The Raspberry Pi shortage has been a meme in hacker circles for what feels like an eternity now, and the Pi 4 seems to be most affected – though, maybe it’s just its popularity. Nevertheless, if you’re looking for a Pi 4, you would need to look far and wide – and things are way worse if you need the 8 GB version specifically. Or so we thought – [MadEDoctor] shows us that refreshing online store pages isn’t the only way, having successfully upgraded the RAM chip on the Pi 4 from 1 GB to 8 GB with help of a hot air gun.

These chips are BGA, and those might feel intimidating if you’re just starting out with hot air – however, we recommend you watch this video, as [MadEDoctor]’s approach is of the kind that brings BGA replacement to hobbyist level. First off, you get a compatible RAM chip somewhere like Aliexpress – lucky for us, those come equipped with a set of balls from the factory. The default balls are made of lead-free solder, and [MadEDoctor] reballed the RAM chip with leaded solder balls to lower the melting point, but it’s by no means a requirement that you do the same.

In fact, you only need a hot air gun, flux, a soldering iron and some solder wick to perform the replacement – no reballing equipment. Put some kapton or metal tape on the board for heat shielding, get the old chip off with hot air, use an iron with wick to clean the pads, add some flux, align the chip, then use hot air to solder a new chip onto the board. Replacing this chip can get your Pi 4 to the highly-sought-after 8 GB target – as an aside, we’re surprised that there was no configuration needed, as the Pi 4 booted right up and successfully recognized the extra RAM added.

We’d personally recommend preheating for such an upgrade – that said, this sure went without a hitch, and such a RAM swap method doesn’t require any stencils, solder paste or solder ball applications. Drop by the video description for compatible RAM chip part numbers, make sure you have your tacky flux and solder wick in order, and let [MadEDoctor] walk you through upgrading your Pi 4 the hacker way. Is this hack to your liking? Take it up a notch with this laptop soldered-in RAM upgrade journey, or that one RAM upgrade for an old GPU to comply to Apple’s whims.

Screenshot from the presentation, showing the datalogger product image next to the datalogger specs stated. The specs are suspiciously similar to those of a Raspberry Pi 3.

Reclaiming A Pi-Based Solar Datalogger

March 4, 2023 by Arya Voronova 7 Comments

There’s quite a few devices on the market that contain a Raspberry Pi as their core, and after becoming a proud owner of a solar roof, [Paolo Bonzini] has found himself with an Entrade ENR-DTLA04DN datalogger which – let’s just say, it had some of the signs, and at FOSDEM 2023, he told us all about it. Installed under the promise of local-only logging, the datalogger gave away its nature with a Raspberry Pi logo-emblazoned power brick, a spec sheet identical to that of a Pi 3, and a MAC address belonging to the Raspberry Pi Foundation. That spec sheet also mentioned a MicroSD card – which eventually died, prompting [Paolo] to take the cover off. He dumped the faulty SD card, then replaced it – and put his own SSH keys on the device while at it.

At this point, Entrade no longer offered devices with local logging, only the option of cloud logging – free, but only for five years, clearly not an option if you like your home cloud-free; the local logging was not flawless either, and thus, the device was worth exploring. A quick peek at the filesystem netted him two large statically-compiled binaries, and strace gave him a way to snoop on RS485 communications between the datalogger and the solar roof-paired inverter. Next, he dug into the binaries, collecting information on how this device did its work. Previously, he found that the device provided an undocumented API over HTTP while connected to his network, and comparing the API’s workings to the data inside the binary netted him some good results – but not enough.

The main binary was identified to be Go code, and [Paolo] shows us a walkthrough on how to reverse-engineer such binaries in radare2, with a small collection of tricks to boot – for instance, grepping the output of strings for GitHub URLs in order to find out the libraries being used. In the end, having reverse-engineered the protocol, he fully rewrote the software, without the annoying bugs of the previous one, and integrated it into his home MQTT network powered by HomeAssistant. As a bonus, he also shows us the datalogger’s main PCB, which turned out to be a peculiar creation – not to spoil the surprise!

We imagine this research isn’t just useful for when you face a similar datalogger’s death, but is also quite handy for those who find themselves at the mercy of the pseudo-free cloud logging plan and would like to opt out. Solar tech seems to be an area where Raspberry Pi boards and proprietary interfaces aren’t uncommon, which is why we see hackers reverse-engineer solar power-related devices – for instance, check out this exploration of a solar inverter’s proprietary protocol to get data out of it, or reverse-engineering an end-of-life decommissioned but perfectly healthy solar inverter’s software to get the service menu password.

Showing balloon rising up, not too far from the ground, with one of the FOSDEM buildings and sky in the background

FOSDEM Sees Surprise Pico Balloon Event

March 4, 2023 by Arya Voronova 23 Comments

At any vaguely-related conferences, groups of hackers sometimes come together to create an impact, and sometimes that impact is swinging something into an airspace of a neighboring country. [deadprogram] tells us that such a thing happened at FOSDEM, where a small group of hackers came together (Nitter) to assemble, program and launch a pico balloon they named TinyGlobo 1, which then flew all the way to France!

This balloon is built around a RP2040, and the firmware is written in TinyGo, a version of Go language for microcontroller use. As is fitting for a hacker group, both the hardware and software are open source. Don’t expect custom PCBs though, as it’s a thoroughly protoboarded build. But a few off-the-shelf modules will get you the same hardware that just flew a 400km route! For build experiences, there’s also a few tweets from the people involved, and a launch video, also embedded below.

This reminds us of the Supercon 2022 balloon story — darn copycats! If you’re interested in the more Earthly details of this year’s FOSDEM open source development conference, check out our recent coverage.

Showing the end result - a Defender machine copy in all its glory, with a colourful front panel with joysticks.

Defender Arcade Rebuilt To Settle A Childhood Memory

March 3, 2023 by Arya Voronova 7 Comments

[Jason Winfield] had a nemesis: the Defender arcade machine. Having put quite a number of coins into one during his childhood, he’s since found himself as a seasoned maker, and decided to hold a rematch on his own terms. For this, he’s recreated the machine from scratch, building it around the guts of a Dell laptop, and he tells us the story what it took to build a new Defender in this day and age.

Defender was a peculiar machine — it was in cocktail table format, unlike many other arcade machines of that period. From pictures, he’s redesigned the whole thing in Fusion 360, in a way more desk-friendly format, but just as fancy looking as before.

As for the laptop, gutting it for its mainboard, screen, and speakers was a surprisingly painless procedure — everything booted up first try. A few board-fitted brackets and a swap from a HDD to a USB flashdrive for the OS later, the electronics were ready. As he was redesigning the entire arcade machine anyway, the new design control panel was also trimmed down for ease of use, while preserving the original colorful look.

All in all, an impressive build from [Jason]. After all was set and done, we don’t doubt that he went on to, let’s say, settle some old scores. It’s not the first time we see a desktop-sized arcade cabinet, and you gotta admire the skills making such a machine smaller while sticking to the old-timey aesthetic! Or, perhaps, would you like a cabinet that’s more subtle?

Continue reading “Defender Arcade Rebuilt To Settle A Childhood Memory” →