WhyCan Forum(哇酷开发者社区)

https://github.com/espressif/esp-hosted

ESP-Hosted solution
ESP-Hosted project provides a way to use ESP32 or ESP32-S2 (termed as ESP peripheral) as a communication processor for Wi-Fi and Bluetooth/BLE connectivity. On the host side, ESP-Hosted offers a standard network interface for receiving and transmitting 802.3 frames. On top of the network interface, the host can use its own TCP/IP and TLS stack. For BT connectivity, a standard HCI interface is exposed to the Bluetooth host stack.

Please note that this project doesn't provide a standard 802.11 interface to the host. For the control path between the host and ESP peripheral, ESP-Hosted uses a custom implementation based on Protobuf.

Connectivity Support
ESP hosted solution provides following WLAN and BT/BLE features to host:

WLAN Features:
802.11b/g/n
WLAN Station
WLAN Soft AP
BT/BLE Features:
v4.2 BR/EDR and BLE
Supported Hosts
ESP-Hosted solution supports microprocessors running Linux as well as STM32 MCU (STM32F469I). It's possible to port this relatively easily on other MCUs too. We support Raspberry-Pi (3 Model B+, 4 Model B) and STM32 Discovery Board (STM32F469I-DISCO) out of the box.

Supported Transports
ESP-Hosted uses SDIO or SPI interface as a transport interface for data and control path. The host acts as SDIO or SPI host whereas ESP32 or ESP32-S2 acts as a corresponding ESP peripheral. Currently Raspberry Pi supports both SDIO and SPI transport and STM32 supports SPI transport. As a peripheral device, ESP32 supports both SDIO and SPI transport interfaces and ESP32-S2 supports SPI transport interface.

For detailed explanation, please go through -

Using Raspberry-Pi as a Linux host
Using STM32F469I-DISCO as a MCU host
Feature Matrix
Linux Host
Below table explains which feature is supported on which transport interface for Linux based host.

ESP device    Transport Interface    WLAN support    Virtual serial interface    BT/BLE support
ESP32    SDIO    Yes    Yes    Yes
ESP32    SPI    Yes    Yes    Yes
ESP32    UART    No    No    Yes
ESP32-S2    SDIO    NA    NA    NA
ESP32-S2    SPI    Yes    Yes    NA
ESP32-S2    UART    No    No    NA
MCU Host
Below table explains which feature is supported on which transport interface for MCU based host.

ESP device    Transport Interface    WLAN support    Virtual serial interface    BT/BLE support
ESP32    SDIO    No    No    No
ESP32    SPI    Yes    Yes    HCI interface can be implemented over virtual serial interface
ESP32    UART    No    No    No
ESP32-S2    SDIO    NA    NA    NA
ESP32-S2    SPI    Yes    Yes    NA
ESP32-S2    UART    No    No    NA