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.
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?
The bare PCB, with the expansion connector bottom centre.
The Tanmatsu (Japanese for “Terminal”), is a general putpose palmtop computer based around an ESP32-P4 application processor from Espressif. It takes the form of a PCB and PETG 3D printed sandwich, with the front face PCB sporting a silicone QWERTY keyboard and an 800×480 MIPI DSI display. The keyboard should be familiar to many readers, being the same moulding as the Solder Party KeebDeck which has appeared on other devices.
Under the hood that P4 has two 400MHz RISC-V cores and 32MB of PSRAM with 16MB of Flash, and there’s an ESP32-C6 for WiFi, BLE and IEEE 802.15.4 mesh networking. There’s an Ebyte LoRa module with an SMA antenna too, which can be had in 868, or 915MHz versions depending on where in the world you live.
For interfacing there are USB A and C ports, and SD card socket, a 3.5 mm jack for audio, and three expansion ports. On the right side a Qwiic compatible socket, on the left a socket with PMOD and SAO capabilities, and on the rear under the cover, a CSI camera connector the same as the Raspberry Pi, and a much larger expansion socket with all the various signals, planned for add-ons. It’s all powered by a chunky 2500 mAh LiPo which can be charged through the USB-C port.
Because I know the folks behind it I’ve watched it grow from its origins in a souped-up version of the MCH2022 badge into its current form, indeed I bought my Tanmatsu just over a year ago. Due to those origins in the Dutch badge team, this device is open-source. The Tanmatsu is a commercial version produced and sold by Renze Nicolai, its designer, while the Konsool is its community cousin. You can find its mechanical hardware here, its electronics here, and its firmware here.
An App Repository For Your Creations
Turning the Tanmatsu on, after a synthwave-inspired splash screen you find yourself in a graphical menu. The user interface is pretty intuitive to anyone used to a desktop GUI or a modern smartphone, along the top are status icons for SD card, Wi-Fi, and battery, the main body of the screen has a grid of icons, and along the bottom is a list of the various keyboard shortcuts. Navigation is via a set of arrow keys with the return key selecting an option, and a set of coloured function keys handle special functions.
Meshcore is only a download from the repository away.
On first start-up the Tanmatsu has no apps installed, so the first order of business is to connect to a Wi-Fi network and update the firmware through the Settings. It takes a while to do this as it can update the firmware on the P4, the C6, and the microcontroller it uses for housekeeping. A feature I like is that this is the first device from the world of badges I’ve seen that can hold more than one set of Wi-Fi network details rather than requiring me to change the settings at each location.
With a freshly updated Tanmatsu you can open the repository, this device’s app store, and download some apps to get started. This is a long-standing badge.team feature, in that badges going back to their SHA 2017 offering have had downloadable apps. The apps are sorted into categories for easy navigation, and in my case there are immediately two apps I have installed, the Tamatype camera app for my Pi camera add-on, and from the choice of two different Meshcore apps, Wadamesh.
The apps themselves come in two forms, either ones written in an interpreted scripting language such as MicroPython, or those compiled directly for the P4. It doesn’t ship with a script engine installed, however MicroPython is downloadable as an app from the repository. This is not a multitasking device so the front-end is a launcher, and after running an app the screen will flash blue for a moment as it loads. Each app has a metadata file which instructs the Tanmatsu what to do with it, an icon file, and a folder containing its executable components. There’s a comprehensive online guide, should you wish to try developing your own apps.
In use the Tanmatsu is convenient to hold and type with using two hands. The display is clear and bright, and the keyboard while a little on the small side has a positive click action. Using the apps depends on the individual choices of the app developer, but the interface conventions are straightforward. I’ve been using it for Meshcore for a while now, and it makes a very handy terminal indeed.
In A Niche Of Its Own
The price of a fully assembled Tanmatsu is 99 Euros, plus Dutch sales tax if you live in the EU, and shipping. The good news for Americans in an age of uncertain tariffs is that I’m told they will be shipping from a US warehouse in the next few months. It’s worth considering for a moment where this places the device in the ecosystem of similar computers.
It’s relatively simple to make a handheld Linux cyberdeck using a Raspberry Pi board, however once the price of new peripherals and parts is taken into account it’s not necessarily a cheap project. There are quite a few similar-sized Linux devices on the market whose prices reflect this at about twice as much. Thus I think that the Tanmatsu fits in a middle zone between development boards that come without the screen, battery, and keyboard, and those Linux handhelds that are all-singing all-dancing.
In its favour it’s as far as I know the only P4 device on the market with a mature operating system and particuarly an app repository, but if only Linux will do, it’s unable to deliver. Where I think its niche lies is in being simple and low power enough to be a reliable and powerful hacker’s communicator and general purpose toolkit, but cheap enough to remain a reasonable purchase. For now it stands alone in that niche, and only time will tell whether it can successfully define it.
Login
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.
