SmartThings SDK Reference for Direct Connected Devices for C

Direct-connected devices connect directly to the SmartThings cloud. The SDK for Direct Connected Devices is equipped to manage all MQTT topics and onboarding requirements, freeing you to focus on the actions and attributes of your device. To facilitate the development of device application in an original chipset SDK, the core device library and the examples were separated into two git repositories. That is, if you want to use the core device library in your original chipset SDK that installed before, you may simply link it to develop a device application in your existing development environment.

It is distributed in source form and written in C99 for the purpose of portability to most platforms. If you want to know the overall workflow of using this SDK, please refer to the Getting Started.

Directory layout

The reference git is delivered via the following directory structure :

apps : sample device applications for each chipset
bsp : An original chipset vendor's SDK is located. If you use a chipset that has already been ported, this vendor's SDK can be easily downloaded as a submodule in this directory through the predefined script(e.g. setup.py).
doc : documents
iot-core : IoT core device library. It can also be downloaded as a submodule in this directory through the predefined script(e.g. setup.py).
output : build outputs will be placed
patches : patches to be applied in the original chipset vendor's SDK for resolving some problems
tools : scripts to be applied for each chipset

Building a sample device application

Basically, this release builds on the environments of chipset vendor's SDKs.

Prerequisites

Install the toolchain defined in the chipset SDK you use. If there is no environmental comment, it is basically only described for 64-bit Ubuntu-based.
- Example for ESP8266 (Ubuntu/Debian quickstart)
  - Setup ESP8266 Toolchain for Linux according to the available Expressif website. In order to use the pre-supplied build script(e.g. build.py), please extract the toolchain into ~/esp/xtensa-lx106-elf/ directory like the original Expressif guide. And according to the above Espressif guideline, you will need to add the toochain path to your PATH environment variable in ~/.profile file. But it is not necessary if you use the pre-supplied build script. Because that path is automatically exported in the build script.
- Example for ESP32
  - Install Prerequisites for your build system OS.
  - Setup ESP32 toolchain by using setup.py
- Example for ESP32_v3.3(legacy) (Ubuntu/Debian quickstart)
  - Setup ESP32 Toolchain for Linux according to the available Expressif website. In order to use the pre-supplied build script(e.g. build.py), please extract the toolchain into ~/esp/xtensa-esp32-elf/ directory like the original Expressif guide. And according to the above Espressif guideline, you will need to add the toochain path to your PATH environment variable in ~/.profile file. But it is not necessary if you use the pre-supplied build script. Because that path is automatically exported in the build script.
- Example for RTL8195
  - Install mbed Microcontroller to use the USB serial port on Windows.
  - Upgrade DAP F/W Recommended DAP F/W is the DAP_FW_Ameba_V12_1_3-2M.bin
    
    Note :
    
    You have to proceed the above steps at Windows PC for downloading a binary. But you have to build the source code on the cygwin or linux for this chipset.
- Example for EMW3166
  - Setup MiCoder Toolchain for Linux according to the available MXCHIP website.
  - Install MiCO Cube In order to use the pre-supplied build script(e.g. build.py), please set mico config --global MICODER /path_of_the_toolchain

Build

Download the Device SDK Reference source code. Basically, this reference will download the ported original chipset vendor's SDKs as submodules in the bsp directory through the setup.py script. If a chipset vendor's SDK does not exist as git format, you can manually copy it under the bsp directory.
- Download the source code via git clone.
- And then, run the setup.py to automatically download submodules to the bsp directory. At this time, the IoT core device library is also downloaded to the iot-core directory.
```
$ cd ~
$ git clone https://github.com/SmartThingsCommunity/st-device-sdk-c-ref.git
$ cd st-device-sdk-c-ref
$ python setup.py
Usage: python setup.py [BSP_NAME]
--------------------------------------------------
ex) python setup.py rtl8721c
ex) python setup.py rtl8720c
ex) python setup.py rtl8195
ex) python setup.py esp32_v3.3
ex) python setup.py emw3080
ex) python setup.py emw3166
ex) python setup.py esp8266
ex) python setup.py esp32
ex) python setup.py esp32s2
```
Check the build configuration of a sample device application. If you want to use specific build options, you can directly modify the build configuration file(e.g. sdkconfig, sdkconfig.h) at the root directory of a sample device application. On the Espressif chipset, you can additionally use the menuconfig option to configure them.
- If you just want to use the default build configuration, you can skip this step.
- Example for ESP8266
  
  Note : The menuconfig option is just supported on the Espressif chipset.
```
# python build.py {app_path} {option}
$ cd ~/st-device-sdk-c-ref
$ python build.py apps/esp32/switch_example menuconfig
```
Run build.py in the SDK's root directory. This builds the sample executables and places them in the output/{chip_name}/.
```
$ python build.py apps/esp32/switch_example          # python build.py {app_path}
```

flash & monitor

Serial port needs to be matched to the computer environment for serial port flashing and monitoring.

Example for ESP8266/ESP32
- Baud rate 115200 for flashing or 74880 for monitoring, Data bit 8, Parity None, Stop bits 1
- These data are described in the build configuration file(e.g. sdkconfig)
Example for RTL8195
- Baud rate 115200, Data bit 8, Parity None, Stop bits 1
Example for EMW3166
- Baud rate 9600 for flashing(user uart) and 115200 for monitoring(USB uart), Data bit 8, Parity None, Stop bits 1

Flashing can be done according to the method supported by chipset SDK.

Example for ESP8266/ESP32

You can flash the executables into a target device via build.py with additional option. Actually, you don't need to run python build.py esp8266 st_switch before running python build.py esp8266 st_switch flash, this will automatically rebuild anything which needs it.
- options
  - clean : clean previous build outputs
```
# python build.py {app_path} {options}
$ python build.py apps/esp32/switch_example clean
```
  - flash : download executable binaries to the device
  - monitor : monitor the serial output of device. this option can be used with flash option.
```
# python build.py {app_path} {options}
$ python build.py apps/esp32/switch_example flash monitor
```
Example for RTL8195

In order to flash the RTL chipset binary, you have to proceed steps below at Windows PC, even though you build the source code on Linux environment.
- Connect Ameba RTL8195 to Windows PC, you can find removable disk named MBED.
- Just copy ram_all.bin in output/rtl8195/iotcore_xxx/ram_all.bin to MBED.
- After copy successfully, please reset Ameba RTL8195 target and monitor
Example for EMW3166

In order to flash the MXCHIP emw3166 chipset binary, you have to proceed steps below at Windows PC, with a terminal support Ymodem transmission.
- Connect user uart(PB7-tx, PB6-rx) of emw3166 to Windows PC with a USB-TTL convertor, and connect USB uart for power.
- Create serial session with flashing config (Baud rate 9600) to connect user uart port, then hold 'BOOT' and press 'RESET' to enable flashing
- Tansfer binary file in output/emw3166/iotcore_xxx/xxx@MK3166.bin with Ymodem on terminal
- After sending successfully, press 'RESET' on MiCOKit-3166 target and monitor with USB uart

License

This library is licensed under the Apache License Ver2.0.

xixidodo / st-device-sdk-c-ref