The Triumph of RISC-V: Why the ESP32 Is Changing Its Architecture

To understand why this transition is so significant, we need to briefly clarify how microcontrollers work. Most processors (such as those in our laptops or smartphones) are based on proprietary instruction set architectures (ISA). When a manufacturer like Espressif wants to build a chip with ARM or Xtensa cores, they have to pay expensive licensing fees to the respective company.

RISC-V (pronounced "Risk-Five"), on the other hand, is a completely open standard. Anyone is allowed to build processors based on RISC-V without having to pay licensing fees. It is essentially the Linux of hardware architectures.

Here is the translation: The classic ESP8266 and the early ESP32 still used cores from Tensilica (Xtensa). With the announcement that exclusively RISC-V will be used in the future, Espressif has made a real bombshell in the industry. There are several good reasons for this:

• No licensing costs: Espressif saves millions in licensing fees. This means for us as end customers: The chips can continue to be offered at extremely low prices (often under 3 euros).
• More control: Since the architecture is open-source, Espressif can tailor the chip precisely to its own needs (e.g. AI computations or extreme low-power mode) without being dependent on updates from a third-party manufacturer.
• Security & Flexibility: An open architecture can be reviewed for vulnerabilities by the global community.

The effects of this change are already being felt in the market. Two of the most popular new boards are already based entirely on RISC-V:

• ESP32-C3: It was positioned as the direct successor to the old ESP8266. It features a single RISC-V core, Wi-Fi, Bluetooth 5 (LE) and is extremely energy-efficient. It is currently the first choice for simple smart home sensors.
• ESP32-C6: The current flagship in terms of connectivity. It not only transmits using the latest Wi-Fi 6 (802.11ax) standard, but also supports Zigbee 3.0 and Thread. This makes it the perfect foundation for Matter-compatible devices in the smart home!

Here is the translation: The good news for all hobbyists: Nothing changes at first.

Here is the translation: The ecosystem surrounding Espressif, most notably the ESP-IDF (Espressif IoT Development Framework) and also the Arduino IDE, completely absorb the architectural change in the background. Your written C++ code or your ESPHome YAML configuration can, in 99% of cases, be compiled seamlessly for a new RISC-V chip without you having to change a single line of code. The compiler (e.g. GCC) simply knows which architecture it needs to translate the ones and zeros for.

Here is the translation: That one of the biggest players in the IoT market is switching its entire product line to open-source hardware is a massive endorsement for RISC-V. For us hobbyists, this primarily means future-proof, extremely affordable, and modern hardware (keywords: Wi-Fi 6 and Zigbee on a single chip). So the next time you buy a development board for your Home Assistant project, take a look at whether it already has a "C3" or "C6" printed on it – because if it does, you're already holding a genuine RISC-V processor in your hands!