It is officially the heart of summer! ☀️ Here are the articles, tools, and announcements that we’ve been excited about since last time.

What have you been reading? Share in the comments or on the Interrupt Slack.

Articles & Learning

• VIC-II Chip Technical Reference | Zimmers.net
   Old-school game development and firmware have a lot in common. – François

• Cloning a Sennheiser BA2015 Accu Pack | brixit
   A deep dive into reverse engineering and recreating a smart battery pack. –  Noah

• Hosting a Website on an 8-bit Microcontroller | Maurycy’s Projects
   A fun tour of serving a website from a tiny microcontroller. – Noah

• Using an LLM to Design a RISC-V CPU | arXiv
   Using an LLM to design a RISC-V CPU (pdf warning). – Noah

• CHERIoT First Silicon | CHERIoT
   The CHERIoT project has first silicon, and  CHERI Linux is also looking workable. – Ash

• How a Broken Bike Sync Led Me to Reverse Engineering My Wahoo’s Hidden Debug Mode
  Reverse engineering the Wahoo ELEMNT Bolt v3 BLE protocol unlocked a hidden debug mode. – Jon

• TLS Encrypted Client Hello (ECH) RFC
  TLS Encrypted Client Hello (ECH) RFC is now published. – Noah

• Intentional flash corruption for STM32 microcontrollers | xarantolus
  Interrupt community member Mo Ger shared that provoking flash corruption in order to test ECCD handling was something they recently needed for work, so this article proved to be quite useful for them!

• The overclocked timer | Mr. PY
  Interrupt community member Andrew Kohlsmith shared that this article was a well-written horror story of an overclocked timer and marathon debug session.

Projects & Tools

• LightInk | Hackaday.io
   Very impressive battery life on an ESP32 watch project, achieved by booting  and running directly from RTC RAM instead of the typical flash boot path. –  Noah

• Xteink X4 with Open Source Firmware | Concretedog
   A small e-ink reader with open source firmware and a nice web flashing tool. – Noah

• Kindle Typewriter | Adafruit Blog
   More e-paper shenanigans. – Jon

• KiCad 10.0.0 Released | KiCad
   Kicad v10.0.0 is out- changes include hopover display for non-connected wires in schematic mode, very nice! – Noah

• Rugix delta update cost-savings calculator
  Rugix has a neat cost-savings calculator. – Ash

• dangdo44/sky130_adder_4bit | GitHub
  Interrupt community member Dangdo shared a hands-on tutorial they developed for embedded developers interested in ASIC design. It covers the manual design flow of a 4-bit ripple-carry adder using the SKY130 open-source PDK and open-source EDA tools.

News & Announcements

• Linux Drivers for the ESP32-E22 Wi-Fi Module | CNX Software
   Espressif’s ESP32-E22 Wi-Fi 6E module gets Wi-Fi certification, along with  open source Wi-Fi and Bluetooth Linux drivers. – Noah

• Web Serial Support in Firefox | Mozilla Hacks
   Web Serial support is finally landing in Firefox. – Ash

• Flattened Image Tree Spec Hits 1.0 | Phoronix
   The Flattened Image Tree (FIT) specification has reached 1.0. – Noah

• Zephyr Cyber Resilience Act Compliance | Zephyr Docs
   Zephyr now has a dedicated page documenting Cyber Resilience Act compliance.

• Embedded World EU 2027 Call for Proposals
  The CFP for Embedded World EU 2027 is open! Abstracts are due September 28th. The conference will be March 16-18 this upcoming year.

Upcoming Events

• Nordic Webinar: Firmware Vulnerability Scanning in nRF Cloud | July 9th, 2026
  We are hosting a webinar for anyone who wants to learn more about our expanding CRA focused offering aimed at helping IoT device manufacturers monitor CVEs in their firmware and understand real fleet exposure. There will be a US session and an EU session. Join us!