What is it?

LoRaWAN Node with a STM32F103C8T6 (Blue Pill) and LoRa Module . One Glove connector (XH2.54 JST 4 Pin) is for an I2C sensor. The other glove connector is directly connected to UART Serial1. This node works with TheThingsNetwork.org and Cayenne Dashboard. Both ABP and OTAA authenticatons are supported.

Why did you make it?

Sometimes you may need more flash memory larger than 64K that ATMEGA328 can give you. This Blue Pill LoRaWAN node is 128K Flash memory. The flash size is big enough for many sensors and you can get more I/O port.

What makes it special?

Preinstalled stm32duino. So, you can use Arduino IDE to flash the program as the same as your Arduino. No need to use ST-Link for flashing. Please specify your country frequency band when you place an order.

STM32F103C8T6 Spec

• ARM 32 Cortex-M3 CPU
• Operating frequency: 72MHz
• 128K Byte Flash, 20KByte SRAM
• Interface Resources: 2x SPI, 3x USART, 2x I2C, 1x CAN, 37x I / O ports,
• Analog-to-digital conversion: 2x ADC (12-bit / 16-channel)
• Timers: 3 general timers and 1 advanced timer
• 3.3V regulator chip, the maximum output of 300mA.
• On-board Mini USB interface
• Number of pins:48
• There is a 5V pin that can be used to supply 5V for a sensor.

LoRaWAN Pin Mapping

.nss = PA4,

.rxtx = 0xFF,

.rst = 0xFF,

.dio = { PA0 , PA1, 0xFF },

How to make your Arduino IDE ready for blue pill.

Go to your browser and open https://github.com/rogerclarkmelbourne/Arduino_STM32 Click Clone or Download/Download Zip. You will get Arduino_STM32-master.zip .

Copy unzip file from Arduino_STM32-master.zip to your sketchbook folder/hardware. Go to arduino IDE menu click File>Preference and you’ll find the location of your sketchbook folder(Ex. C:\Users\Documents\Arduino). If there’s no hardware folder, create one named as “hardware” (all lowercase letter). Re-open your Arduino IDE and now it ready for Blue pill.

Open Arduino IDE. Go to Tools>board> Generic STM32F103C Series. Then go to Tools>Variant>STM32F103C8 (20k ram, 128k flash). Go to tools> upload method>STM32duino bootloader. Select your Port ComX (Maple Mini) and Optimize Smallest.

LoRa Module main Chip is H RF96 or SX1276.

What item are included in the order.

• One 10 cm. long antenna that correspond with your selected freq. (Antenna might look difference from the showed picture.)
• PCB board with STM32 Blue Pill.

Hint!

In case you find an error message "'_FDEV_SETUP_WRITE' was not declared in this scope.". Open config.h in LMIC Library. Put comment before this line.

//#define LMIC_PRINTF_TO Serial

You can find your LMIC config.h file in similar directory such as C:\Users........\Documents\Arduino\libraries\arduino-lmic-master. Replace ..... with your username on your PC.

Important Notice

Don't add STM32 board by using this Github. https://github.com/stm32duino/Arduino_Core_STM32. It does not provide upload method>STM32duino bootloader. Choose other upload method will overwrite existing STM32duino Bootloader.