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Running Bare-Metal Rust Alongside ESP-IDF on the ESP32-S3's Second Core

38 pointsby MrBuddyCasinolast Friday at 4:57 AM7 commentsview on HN

Comments

the__alchemisttoday at 12:09 AM

Very good article!

Anecdote about this summary at the bottom: > This setup gives you the best of both worlds: ESP-IDF and FreeRTOS manage Wi-Fi, BLE, and system tasks on Core 0, while Core 1 runs your bare-metal Rust code at full speed with zero scheduler interference.

I am doing something somewhat like this, but with separate MCUs instead of separate cores. I flashed Esp-Hosted-MCU onto an ESP-32 (C3, but any including S3 will work). This is official firmware which turns the ESP into a "radio co-processor", so you can treat it like a SPI or UART Wi-Fi/BLE chip.

On another MCU (STM32), I run bare-metal firmware in rust which talks to the radio over SPI. Wi-Fi uses the ESP IDF, and BLE uses standard HCI commands.

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fjfaaseyesterday at 11:04 PM

I think you can run a single task on core 1 without interference if you give it the right priority (and disable some things).

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dakollitoday at 2:19 AM

This is a great blog, I love the I Built a WebAssembly Runtime in 5 Days Because I Was Tired of Paying for Cloud Run [1], . You do a great job at showcasing your creativity for solving problems. I can tell that you genuinely got a lot of satisfaction from escaping big cloud FaaS, for literally fun and profit. I need more blogs like this.

[1]: https://tingouw.com/blog/cloud_notes/badwater_intro#day-5-8m...

ufociatoday at 1:55 AM

Interesting, but giving up an entire core to Wi-Fi and Bluetooth seems wasteful.

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