NB-IoT GPS Tracker running on the Ghostyu NB-EK-L476 Developer Kit with STM32L476RCT6 microcontroller, Quectel L70-R GPS module and Quectel BC95 NB-IoT module. Photo taken during the field test at Berlayer Creek Boardwalk in Singapore.

Install Apache Mynewt and Embedded Rust for STM32 L476 and Visual Studio Code on Windows

Lup Yuen Lee 李立源

Sep 22, 2019·6 min read

Follow these instructions to install Apache Mynewt + Embedded Rust build and application files for STM32 L476 and Visual Studio Code on Windows for the article “Build an NB-IoT GPS Tracker on STM32 L476 with Apache Mynewt and Embedded Rust”

Install Rust

1️⃣ Click here to install Build Tools For Visual Studio 2019:
https://visualstudio.microsoft.com/downloads/#build-tools-for-visual-studio-2019

2️⃣ Click the Individual Components tab

Select the following components:

Windows 10 SDK (10.0.18362.0)
C++ CMake Tools for Windows
(This should be automatically selected) MSVC v142 — VS 2019 C++ x64/x86 Build Tools

3️⃣ Install rustup according to the instructions here:
https://rustup.rs

Click the link provided to download rustup‑init.exe

Launch the downloaded file rustup‑init.exe

If you see the message “Windows Defender SmartScreen prevented an unrecognised app from starting”…

Click More Info

Click Run Anyway

4️⃣ At the Welcome to Rust! prompt, press Enter to select the default option:
1) Proceed with installation (default)

5️⃣ Open the Windows Command Prompt. Enter into the command prompt:

rustup default nightly
rustup update
rustup target add thumbv7m-none-eabi
rustup target add thumbv7em-none-eabihf
rustc -V

The reported version of rustc should be 1.38.0 or later:

rustc 1.38.0-nightly (435236b88 2019–08–01)

Install Source Files and Build The Firmware

1️⃣ Download the stm32bluepill-mynewt-sensor.7z file attached below…
https://github.com/lupyuen/stm32bluepill-mynewt-sensor/releases/tag/v9.0.0

Expand the .7z file with 7zip…
https://www.7-zip.org/download.html

2️⃣ Install Arm Cross-Compiler and Linker for Windows from Arm Developer Website…
https://developer.arm.com/-/media/Files/downloads/gnu-rm/8-2019q3/RC1.1/gcc-arm-none-eabi-8-2019-q3-update-win32-sha1.exe?revision=fcadabed-d946-49dc-8f78-0732d2f43773?product=GNU%20Arm%20Embedded%20Toolchain,32-bit,,Windows,8-2019-q3-update

Select this option at the last install step:
"Add path to environment variable"

3️⃣ Download the ST-Link USB driver from ST-Link Driver Website (email registration required)…
https://www.st.com/en/development-tools/stsw-link009.html

Click Get Software
Unzip the downloaded file. Double-click the driver installer:
dpinst_amd64.exe

4️⃣ Install Windows Studio Code:
https://code.visualstudio.com/

Launch Visual Studio Code

Install the extension “Cortex-Debug”…
https://marketplace.visualstudio.com/items?itemName=marus25.cortex-debug

5️⃣ Click File → Open Folder
Select the downloaded folder stm32bluepill-mynewt-sensor

When prompted to open the workspace, click Open Workspace

6️⃣ If you have a Quectel NB-IoT module…

Open the following file and configure the program settings:
targets/stm32l4_my_sensor/syscfg.yml

Change the NB-IoT band setting NBIOT_BAND. Check with your NB-IoT operator for the band to use. The other settings are documented below.

7️⃣ Click Terminal → Run Task → [1] Build Bootloader
This builds the bootloader, which starts the Apache Mynewt operating system upon startup. If it shows errors, compare with this build log.

Click Terminal → Run Task → [2] Build Application
This builds the firmware containing our Rust program. Compare with this build log.

When our Rust program has been successfully compiled as STM32 ROM firmware, we should see this…

If you see the message Undefined reference to main, rebuild the application by clicking Terminal → Run Task → [2] Build Application

Click Terminal → Run Task → [3] Image Application
This creates the flash image from the firmware. Compare with this image log.

If any source files or configuration files are changed, rebuild the application by clicking Terminal → Run Task → [2] Build Application

Flash The Firmware

The next step is to flash the firmware into ROM. We’ll need to connect the STM32 L476 board to the USB port of our computer via an ST-Link V2 adapter.

1️⃣ Check that the STM32 L476 board is connected to ST-Link… And that the ST-Link is connected to your computer’s USB port.

2️⃣ Click Terminal → Run Task → [4] Load Bootloader

This flashes the bootloader, to start the Apache Mynewt operating system upon startup. If it shows errors, compare with this flash log.

3️⃣ Click Terminal → Run Task → [5] Load Application

This flashes the application firmware. If it shows errors, compare with this flash log.

Run The Program

1️⃣ Click Debug → Start Debugging

2️⃣ Click View → Output

Select Adapter Output to see the Console Log of debug messages generated by our program

3️⃣ The debugger pauses at the line with LoopCopyDataInit

Click Continue or press F5

4️⃣ The debugger pauses next at the main() function.

Click Continue or press F5

The Console Log should look like this.

Rust Source Files

The Rust source files are located in the rust folder…

rust/app: Rust application that polls the internal temperature and GPS sensors and transmits the sensor data over NB-IoT

rust/visual: Sample Visual Embedded Rust program. Not used in this tutorial.

rust/mynewt: Rust Safe Wrappers for Mynewt OS and libraries

rust/macros: Rust Procedural Macros for generating Safe Wrappers and other utility macros like strn!()

Optional: Install Rust Language Server

To get full Rust Language Support for editing Rust source files in Visual Studio Code, you may install Rust Language Server…

1️⃣ In Visual Studio Code, browse to a Rust file like rust/app/src/lib.rs

2️⃣ When prompted to install RLS, click Yes

3️⃣ Good Luck! Sometimes the RLS installation fails with this message because we are using the nightly build…

Optional: Program Settings

The program settings may be found in the file targets/stm32l4_my_sensor/syscfg.yml

	syscfg.vals:
	###########################################################################
	# CoAP Server Settings

	# CoAP host e.g. 104.199.85.211 (for coap.thethings.io)
	COAP_HOST: '"104.199.85.211"'

	# CoAP UDP port, usually port 5683
	COAP_PORT: 5683

	# CoAP URI e.g. v2/things/IVRiBCcR6HPp_CcZIFfOZFxz_izni5xc_KO-kgSA2Y8 (for thethings.io, the last part is the Thing Token)
	COAP_URI: '"v2/things/IVRiBCcR6HPp_CcZIFfOZFxz_izni5xc_KO-kgSA2Y8"'

	###########################################################################
	# Network Settings

	DEVICE_TYPE: '"l476"' # Device type that will be prepended to the Device ID. thethings.io converts the raw temperature depending on the device type.
	NBIOT_BAND: 8 # Connect to this NB-IoT band
	SENSOR_NETWORK: 1 # Enable Sensor Network library
	SENSOR_COAP: 1 # Send sensor data to CoAP server
	COAP_CBOR_ENCODING: 0 # Disable CBOR encoding of CoAP payload
	COAP_JSON_ENCODING: 1 # Use JSON to encode CoAP payload for forwarding to thethings.io
	RAW_TEMP: 1 # Use raw temperature (integer) instead of floating-point temperature values, to reduce ROM size

	###########################################################################
	# Hardware Settings

	HARDFLOAT: 1 # Enable hardware floating-point support for STM32L476RC
	LOW_POWER: 0 # Disable low power support

	UART_0: 1 # Enable USART2 for GPS module
	UART_1: 0 # Disable USART1
	UART_2: 1 # Enable USART3 for NB-IoT module
	UART_2_SWAP_TXRX: 1 # Swap TX/RX pins for USART3 so that USART3 behaves like LPUART1

	GPS_L70R: 1 # Enable driver for Quectel L70R GPS module
	GPS_L70R_UART: 0 # Connect to Quectel L70R module on USART2
	GPS_L70R_ENABLE_PIN: MCU_GPIO_PORTA(1) # GPIO Pin PA1 enables and disables the GPS module. Set to -1 for no pin.

	BC95G: 1 # Enable driver for Quectel BC95-G NB-IoT module
	BC95G_UART: 2 # Connect to Quectel BC95-G module on LPUART1 i.e. USART3 with TX/RX pins swapped
	BC95G_ENABLE_PIN: MCU_GPIO_PORTA(0) # GPIO Pin PA0 enables and disables the NB-IoT module. Set to -1 for no pin.

	ADC_1: 1 # Enable port ADC1
	TEMP_STM32: 1 # Enable STM32 internal temperature sensor
	HMAC_PRNG: 1 # Enable HMAC PRNG pseudorandom number generator

view raw syscfg-l476.yml hosted with ❤ by GitHub

Program Settings. From https://github.com/lupyuen/stm32bluepill-mynewt-sensor/blob/l476/targets/stm32l4_my_sensor/syscfg.yml

COAP_HOST, COAP_PORT: The program will send CoAP messages to this IP address and port number, which defaults to the CoAP server at thethings.io.

Keep the default settings if you wish to view your sensor data at blue-pill-geolocate.appspot.com.

Change the setting to use your own CoAP server instead of thethings.io

COAP_URI: The CoAP message will be delivered to this URI at the CoAP server (which defaults to thethings.io).

Keep the default settings if you wish to view your sensor data at blue-pill-geolocate.appspot.com.

For thethings.io, the last part IVRi… is the Thing Token. If you wish to send sensor data to your own Thing at thethings.io, replace the last part of the URI with your Thing Token.

For the purpose of NB-IoT Education, I’ll allow you to transmit sensor data to the Thing Token IVRi… from my personal, paid thethings.io account. Which will forward the sensor data to blue-pill-geolocate.appspot.com for viewing.

NBIOT_BAND: The program connects to this NB-IoT Frequency Band. The Frequency Band depends on your country and your NB-IoT network operator. Check with your NB-IoT network operator for the Frequency Band to use.

NB-IoT Frequency Bands for Singapore. From https://www.imda.gov.sg/-/media/imda/files/regulation-licensing-and-consultations/frameworks-and-policies/spectrum-management-and-coordination/spectrummgmthb.pdf

NB-IoT Frequency Bands for Singapore. From https://www.imda.gov.sg/-/media/imda/files/regulation-licensing-and-consultations/ict-standards/telecommunication-standards/radio-comms/imda-ts-iot.pdf