The hosted component allows Sming’s host emulator to run parts of the commands on an actual microcontroller. The communication is done via simplePRC and the microcontroller has to be flashed with a special application.


Sming’s host emulator allows easier debugging and development of embedded applications. This component named “Hosted” extends the host emulator and facilitates testing functionality that only a real microcontroller can provide as for example digital I/O operations or SPI operations.

For example in order to run the Basic_Blink application under the host emulator and run the actual blinking of a LED on a microcontroller we can compile the application using the following directives:


SMING_ARCH=Host instructs the build system to build the application for the Host architecture. ENABLE_HOSTED=tcp instructs the host emulator to communication with the real microcontroller using TCP HOSTED_SERVER_IP= instructs the host emulator to connect to IP

We need to compile and flash also a special application on the desired microcontroller. This application will act as an RPC Server and will execute the commands from the host emulator on the microcontroller.

In the sub-directory samples inside this directory you will find the sample applications that will turn your microcontroller into RCP server.

The compilation and flashing for ESP32, for example, can be done using the following commands:

cd samples/tcp
make flash

If you replace SMING_ARCH=Esp32 with SMING_ARCH=Esp8266 then the hosted application will be compiled and flashed on a ESP8266 microcontroller. Make sure to replace the values of  WIFI_SSID and WIFI_PWD with the actual name and password for the Access Point (AP).


At the moment the communication between an application running on the Host and the RCP server running on a microcontroller can be done using TCP or serial interface. The transport classes are located under include/Hosted/Transport.



Default: empty (disabled)

Enables the hosted component. Valid values for the moment are: - tcp - for communication over TCP network. - serial - for communication over serial interface



Used only when ENABLE_HOSTED=tcp is specified. Specifies the IP address of the remote RPC server.


Default: /dev/ttyUSB0 or the value of the environment variable COM_PORT if defined

Used only when ENABLE_HOSTED=serial is specified. Specifies which local communication port should be used to connect to the remote RPC server.


Default: 115200

Used only when ENABLE_HOSTED=serial is specified. Specifies the communication baud rate.


Used by

Environment Variables