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• March 2025 progress update
• Tanmatsu can now be pre-ordered

Tanmatsu

March 2025 progress update

March 2025 progress update

A lot has happened since our last blog post in January and we have got a lot of good news to share!

The project is still progressing according to schedule and the first parts of Tanmatsu have arrived.

Displays

We have received a shipment of LH397K-IC01 displays for the first batch of Tanmatsu boards. We’re really happy with how smooth the communication with the manufacturer went and that delivery of the package went without a hitch.

Batteries

It took a bit of effort to get the manufacturer to send us all the documents we need for compliance, but we are pleased to announce that the batteries for Tanmatsu have arrived and are ready for use in production.

The batteries Tanmatsu will ship with are 2500mAh batteries manufactured by Tewaycell. We have built up quite a lot of experience with the products of this manufacturer as we’ve succesfully used their batteries for many projects we have done with Badge.team over the past 10 years.

These batteries have a built-in protection circuit protecting the battery against over-current as well as under and over voltage conditions. By using these protected cells we can make sure that no matter what happens in the circuit on the mainboard the battery will be safely shut down if disaster strikes. And of course this circuit will automatically recover the normal battery functionality after the fault clears.

The batteries are fitted with a JST compatible PH-2.0 type connector. This connector with 2mm spacing between the pins is the same connector used by Adafruit and Sparkfun on most of their battery compatible development boards.

Keyboards

The keyboards have been ordered at the manufacturer (Solder Party) and are on their way to us right now.

ESP32-P4

The ESP32-P4 chip around which Tanmatsu has been designed is brand new and not yet available through all the regular electronic part distributors. Luckily this doesn’t mean we have to wait much longer: Espressif has contacted us to confirm they will be able to deliver the chips we need for the first production round very soon. Of course we will notify everyone once the ESP32-P4 chips have arrived at the factory to be used in production of the Tanmatsu mainboards. Join our Discord or Telegram community chat groups to be among the first to know when we receive the chips.

Compliance

Getting Tanmatsu fully compliant with both European (CE, UKCA) and FCC regulations has proven itself to be quite a challenge. Not because of any technical problems but because of the amount of extra administrative work building proper compliance documentation entails.

Besides the administrative work we have succesfully executed some initial pre-compliance tests to make sure Tanmatsu is not affected by external noise sources and we’ve checked that we do not see signs of unwanted noise being generated by Tanmatsu itself. Of course these initial tests are not conclusive and only a first step in what will be a long process.

The process of getting Tanmatsu compliant has caued a small change in the design, we have replaced the AI Thinker LoRa modules we originally planned on using with functionally equivalent Ebyte E22-900M22S and E22-400M22S modules. While these modules contain exactly the same LoRa radio there is one important difference to note: they come with CE and FCC certification. This means it will be less work to pass CE compliance testing once we are ready to start the lab tests.

Mechanical design

The mechanical design of the case Tanmatsu will ship with has seen some improvements over the past weeks. We have integrated pockets to hold the battery and speaker in place without using any glue to hold them down in the case. This allows you to easily replace the case with a different one without having to worry about transferring the battery or speaker. We will release the step and stl files for modifying and printing your own cases once Tanmatsu starts shipping. Can’t wait? Get in touch and tell us what you’re planning to do on Discord or Telegram.

Availability of spare parts

An open source project is only truely open if it’s possible for everyone to build the project themselves. Additionally we also value the ability of our customers to repair the products they buy, we value the right to repair and will make all parts you need to repair your Tanmatsu available. You can expect to find the display, battery and keyboard along with new 3D printed spacers, cases, frontpanels and even the nuts and bolts used to manufacture Tanmatsu to be listed in our webshop after the first batch of Tanmatsu boards starts shipping.

Tanmatsu can now be pre-ordered

Pre-ordering is now possible through our new webshop

Tanmatsu can now be pre-ordered for € 120 including VAT (€99,17 without VAT for customers outside of the EU). You can pre-order the Tanmatsu via our new webshop.

Project progress

The final prototypes are currently being manufactured over at JLCPCB. Meanwhile we are working on the launcher firmware which will allow users to install and run firmware binaries like apps. The launcher menu shows a list of installed apps (firmwares). When an app is selected the ESP32-P4 will reboot into the selected app.

AppFS is a combination of a firmware “filesystem” and an addition to the bootloader which allows installing and starting multiple firmwares dynamically. It was created originally as a way to install multiple applications on the PocketSprite keychain gameconsole. In 2022 we used the AppFS component as the core of the MCH2022 event badge launcher firmware.

Since then we have in collaboration with the awesome people from Badge.Team updated the AppFS code to make it work with the latest ESP-IDF revision and we have added support for the ESP32-C6 and ESP32-P4. We have published the updated and improved AppFS component which forms the basis of the Tanmatsu launcher firmware on GitHub and the ESP component registry.

The MCH2022 badge application launcher menu:

While waiting on the ESP32-P4 to become available in larger quantities, we will be working on finishing a fully featured launcher firmware for the Tanmatsu with OTA firmware updating support. Follow our website for updates and join our community channel on Telegram or Discord to be kept up-to-date with our progress.

Page updates

• 13-02-2025: the expected release date mentioned in this post has been removed. Tanmatsu will be shipped after the ESP32-P4 chip becomes available and regulatory compliance testing of the product has been succesfully concluded.