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.
sottol 2 hours ago [-]
Interestingly, Espressif nowadays does something similar on the ESP32-P4 which is RiscV but doesn't have builtin Wifi/BT. So they tend to pair it with an ESP32-C6 which runs the WiFi stack and firmware that communicates with the P4 using SDIO. Not bare metal though, but similar dual-mcu setup for wifi/bt.
fjfaase 4 hours ago [-]
I think you can run a single task on core 1 without interference if you give it the right priority (and disable some things).
barbegal 3 hours ago [-]
Yes you can pin it to core 1 whilst pinning all other tasks to core 0. Then will never be interrupted or preempted (except by interrupts created on core 1)
dakolli 36 minutes ago [-]
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.
Interesting, but giving up an entire core to Wi-Fi and Bluetooth seems wasteful.
the__alchemist 33 minutes ago [-]
This is reasonably common - Nordic and ST do this as well on the nrf-53 and STm32WB/L respectively. It's convenient for concurrency, and separation of concerns.
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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.
[1]: https://tingouw.com/blog/cloud_notes/badwater_intro#day-5-8m...