This DIY Time Server Is More Accurate Than You Need

July 8, 2026 by Tom Nardi 25 Comments

You almost certainly don’t have an application for the sort of accurate timekeeping that’s made possible by this enhanced version of [Cristiano Monteiro]’s satellite-backed time server. By his own admission, the vast majority of users will be more than happy to have their system’s time synchronized by the traditional Network Time Protocol (NTP). But if you’re really chasing those last few microseconds, that’s where the Precision Time Protocol (PTP) comes in.

With NTP, you can get within 10 milliseconds or so of your upstream time source — but PTP is accurate down to nanoseconds. Unless you’re performing some kind of scientific research, running a robotic assembly line, or perhaps doing high-speed financial trading, there’s no reason for this level of accuracy. In fact, PTP is such a niche technology that until the release of the ESP32-P4, [Cristiano] couldn’t even find an affordable enough chip that supported it.

Hardware-level support for PTP is important as there’s no way to achieve this level of accuracy with software alone, the capability needs to be baked into the Ethernet controller. As you might expect, it takes a highly accurate time source to make the most of PTP, and that’s where the navigation-grade Global Navigation Satellite System (GNSS) receiver comes in. All told the cost of the build is unsurprisingly higher than that of its predecessor, but [Cristiano] says it’s still a couple zeros shy of what a commercial offering would run.

As with his original time server from 2021, [Cristiano] made sure this build was as friendly as possible for hackers and makers. We especially like the 3D printed case designed in OpenSCAD, and his insistence that the gadget have a front panel with blinking status LEDs. Again, the vast majority of us don’t need our clocks to be accurate down to the nanosecond…but it’s nice to know we have the option.

ESP32 Keeps Tabs On Your Local Airspace

July 8, 2026 by Tom Nardi 21 Comments

We know, we know. Despite being called ESP32-Plane-Radar, this project from [Mateusz Juszczyk] isn’t actually using radar. But thanks to the round LCD this desktop gadget does a fantastic job of recreating a classic radar display, and by pulling in Automatic Dependent Surveillance–Broadcast (ADS-B) data, the visuals even match nearby real-world aircraft.

Perhaps the best part of this project is just how easy it is for others to get in on the action. Although the presentation certainly looks professional — and expensive, if we’re being honest — there’s nothing particularly exotic going on here. Specifically, there’s ESP32-C3 Super Mini behind the scenes cranking through the ADS-B data and pushing it out to a circular GC9A01 display. A minimalistic 3D printed enclosure holds both components, and while it’s undeniably slick as-is, we can’t help but think there’s potential here for more elaborate designs.

As you probably guessed from the lack of a radio in the parts list, the code [Mateusz] provides doesn’t actually sniff ADS-B out of the air. It connects to the local network over WiFi, and then hits adsb.fi to pull in crowdsourced flight data. Since the device has to connect to the network anyway, the code also offers up a web-based configuration interface which puts a little more polish on what’s already an impressive presentation.

We used a round GC9A01 display on the Vectorscope back in 2023, so if anyone ports this over to their old Supercon badge we’d love to see it in action.

Thanks to [Mauricio] for the tip.

Gluing 8192 MCUs Together To Make A GPU

July 6, 2026 by Maya Posch 27 Comments

What do you get when you take 8,192 CH570 MCUs, put them on custom PCBs, and write firmware for this interconnected gaggle of cores? In the case of [bitluni]’s project, you get something that’s decidedly cluster-shaped.

These cheap MCUs feature a QingKe 32-bit RISC-V core that’s clocked at a maximum of 100 MHz, with an RV32IMBC instruction set. This means that they support integers, integer multiplication and division, bit manipulation, and compressed instructions, but no atomic, vector, or floating-point instructions.

The basic concept was to use a single MCU per pixel, but once you start scaling up a measly 10 mA and ~$0.10 per MCU to literally tens of thousands of them, you’re suddenly talking about thousands of dollars in hardware as well as a cool 655.36A at 3.3V – or 2 kW – for something close to QVGA resolution at 320×200. Clearly this would be a rather crazy project to implement, which is why each MCU also got its own RGB LED to immediately create the pixel.

Continue reading “Gluing 8192 MCUs Together To Make A GPU” →

This KVM Runs A P4 Instead Of A Pi.

July 3, 2026 by Tyler August 16 Comments

If you asked us to build you a KVM last week, we’d likely have reached for a Raspberry Pi. Now, thanks to [JonathanRowny], we’d seriously consider an ESP32-P4, because his IP KVM seems pretty capable.

He’s using the P4 hardware to its fullest, getting the supported 1080p graphics, and doing so in an interesting way– he’s got a commercial adapter board to try and translate HDMI signals to the camera input on his dev board. Conveniently enough, it’s the same ribbon-cable pinout as the RPi, which is not guaranteed by the CSI standard. Writing a driver to take that signal proved the hardest part– aside from the usual chip revision confusion that plagues this chip– and we can’t help but wonder if the client on the other side of the KVM-IP link might have an easier time doing the image processing that was required for a good image. Regardless, he’s got the code as it is now up on GitHub under the Apache license.

As of this this writing, there’s no audio, and ironically for an ESP32 project networking is wired-only– but much more importantly, there is no security. So it’s a work in progress, but great to see the P4 in the wild doing something other than emulation. Not that we haven’t seen the P4 at work before–the Tanmatsu handheld also makes use of Expressif’s most powerful chip for a handy little terminal. Between the KVM and the handhelds, we cannot help but wonder how many of the projects that were once the provenance of a Pi will get squeezed into these overpowered microcontrollers. Sure, they can’t even match the original Pi in horsepower, never mind a modern Pi5, but how many times have you seen a Linux SBC seriously under-taxed in a project like this?

If you’re swapping Pi for P4– or doing anything else interesting– please let us know on the tips line.

Continue reading “This KVM Runs A P4 Instead Of A Pi.” →

CSS On The ESP32

June 25, 2026 by Zoe Skyforest 14 Comments

There are lots of graphics libraries available for the ESP32, and lots of ways to program one to boot. Even still, most of us wouldn’t immediately think to CSS when it comes to embedded products — yet that’s now a thing on the Espressif platform, apparently.

The Gea stack allows one to compose CSS and TypeScript code that is then turned into generated C++ code that compiles to native firmware. The team behind Gea have demoed this ability by running a 3D cube animation on an ESP32 at up to 60 FPS. This isn’t some ugly, low-res wireframe demo, either. It’s a full-color animation running on a 410×502 AMOLED screen. It’s very fluid, and can even handle transparency on the cube faces (albeit with a performance penalty).

It’s worth noting that this isn’t a full browser engine. As you might expect, some concessions had to be made to get it running on the ESP32. Namely, it doesn’t handle “:hover” states because it’s designed for touchscreen use, fonts are rasterized, and the UI tree is limited to just 512 nodes. Regardless, it shows that using CSS and TypeScript to develop for the ESP32 is entirely possible without some crazy loss of performance. If you want to build easy interfaces on an ESP32 while leaning on web dev experience, this could be very useful indeed.

There are lots of fun ways to write code for the ESP32; you can even try MicroPython if you like.

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A BIOS For Your ESP32-C6

June 23, 2026 by Jenny List 24 Comments

An old-style PC BIOS served the function of a bootloader in loading the operating system kernel, and of an API in providing a set of standard system calls through which software could interact with the hardware. Though it as been long-ago superseded by operating system level calls and UEFI bootloaders, it was a simple and easy-to-understand firmware for the PCs of the day.

Microcontrollers usually don’t have anything quite like a BIOS because their software is more often compiled as-is without the need for one. But here’s [Rompass] who has bucked that trend, with a BIOS for the ESP32-C6.

Of course this isn’t the PC BIOS we all know, and you’ll not be running DOS on it. Instead it’s a subsystem that serves the purposes outlined above and provides an environment for dynamically loaded executables from RAM rather than an operating system kernel. The executables are compiled in the normal way for the ESP32, and can be loaded over the network if necessary.

We don’t know how popular a firmware like this one will become, but for us it’s symptomatic of how the line between a microcontroller and a microprocessor is becoming blurred. The next few years are going to continue this trend, as inexpensive microcontroller application processors such as the C6’s P4 bigger brother move into the mainstream.

Header image: Popolon, CC BY-SA 4.0.

Skip The Embedded Filesystem With The TAR-like UTFS Format

June 17, 2026 by Maya Posch 11 Comments

If you need to store some data on a resource-constrained embedded platform, the prospect of dragging in a dependency for something like FAT filesystem access to flash or other storage medium can seem rather daunting. Not only is your binary size now significantly larger, the overhead of these filesystems is also not insignificant as they were not really designed for this type of environment. Here [Drew Gaylo]’s UTFS format is an interesting alternative to just writing raw binary data to said storage medium.

As explained in the accompanying introduction article, the basic idea is similar in scope but very much slimmed down compared to the venerable Tape ARchive (TAR) format, hence the Micro (µ) Tar File System name. The provided UTFS implementation is quite small, spanning two source files in C99 with zero heap usage. Targeting a custom store medium requires implementing one read and one write function to match the underlying platform.

A couple of examples are also provided, covering using the built-in Flash of a SAMD20 MCU and the EEPROM of an ATmega328. Compared to raw binary data that’d have to be fully rewritten, UTFS allows for sections of the storage to be accessed as files and thus updated in-place.