lorawan-basic-cookbook

step by step to interface your lorawan for any STM32 mcu & SX1276

• 1, platform: STM32CubeIDE V1.3 or V1.2 https://www.st.com/en/development-tools/stm32cubeide.html
• 2, initialize project by CUBEMX
• 3, RCC -> enable RCC HSE and LSE(for RTC)

  go to Clock Configuration, set LSE 32.768 source for RTC

• 4, RTC -> active RTC source, active Calender,

  Hour Format = 24H, AsynchPrediv = 3, SynchPrediv = 3; Calender time Format = BIN data, DaylightSaving OFF, Storeoperation RESET; no alarm

• 5, set 4 gpio external interrupt and rename as LORA_D0, LORA_D1, LORA_D2, LORA_D3,

  go to NVIC, check related interrupt EXT line, make sure all EXT lines are not enabled

• 6, set gpio reset pin LORA_RST, spi nss pin LORA_NSS, to OUTPUT, PUSH-PULL, output HIGH
• 7, set SPI, full-duplex master,

  use default 8-bit, MSB first, CPOL = LOW, CPHA = 1 Edge, use software NSS change prescaller, set baudrate to 2 Mbits/s

• 8, go to project setting -> code generator tab, tick Generate peripheral initialization as a pair of ".c/.h" ...
• 9, save and generate code
• 10, copy folder mac, board, sx1276 to project root folder, copy lorawan.h to Core/inc, copy lorawan.c to Core/src
• 11, IDE -> project -> properties, go to C/C++ general -> path and symbols,

  go to includes, add -> input mac, then add mac/crypto, board and sx1276 go to Source location, add folder -> select mac, board and sx1276 go to Symbols, add name USE_BAND_915, the value just leave empty apply, apply and close

• 12, edit board.h, check line #include "stm32l1xx_hal.h", make sure it fits your stm32 mcu series, otherwise change it.
• 13, edit main.c

  #include "board.h" #include "lorawan.h" add static Gpio_t led1; before main()

• 14, change board.h gpio pin definitions based on your demo board

  #define RADIO_DIO_0                                 PB_10
  #define RADIO_DIO_1                                 PB_2
  #define RADIO_DIO_2                                 PB_0
  #define RADIO_DIO_3                                 PB_1
  
  #define RADIO_RESET                                 PB_11
  
  #define RADIO_NSS                                   PA_4
  #define RADIO_SCLK                                  PA_5
  #define RADIO_MISO                                  PA_6
  #define RADIO_MOSI                                  PA_7

• 14-1, test gpio output functions

  add GpioInit( &led1, PB_8, PIN_OUTPUT, PIN_PUSH_PULL, PIN_NO_PULL, 0 ); before main while, (assume PB_8 control LED of your demo board) add GpioWrite(&led1, 1); compile and run the code, if the LED got light up, congratilations! go to step 15, otherwise fix errors possible compile error issue: GpioMcuSetInterrupt() -> exi irq name and Board_Init() -> alarm irq name, different series of mcu got different interrupt definition, refer the stm32 header file.

• 15, test gpio interrupt functions, add code after led1 definition,

  static void keyCallback(void){
      GpioToggle(&led1);
  }
  static Gpio_t key;
  DioIrqHandler *keyHandler = keyCallback;

  add code after led1 initialization, assume PA_12 pin is input of your demo board

  GpioInit( &key, PA_12, PIN_INPUT, PIN_PUSH_PULL, PIN_PULL_UP, 0 );
  GpioSetInterrupt( &key, IRQ_FALLING_EDGE, IRQ_HIGH_PRIORITY, keyHandler );

  compile and run the code, if short pin PA_12 to GND, you will see led light flip, congratilations! go to step 16, otherwise fix errors possible miss interrupt error issue: board-gpio.c, EXTI0_1_IRQHandler, HAL_GPIO_EXTI_Callback, different series mcu might have different default names

• 16, test RTC timer interrupt functions, add code after led1 initialization,

  Board_Init();
  uint32_t t = Board_Timer_Test(2000);
  if((t>2000 && t-2000<5)||(t<2000 && 2000-t<5)||(t==2000)){
    GpioWrite(&led1, 0);
  }

  compile and run the code, if the led flip, congratilations! go to step 17, otherwise fix errors possible miss interrupt error issue: board-timer.c, RTC_Alarm_IRQHandler, different series mcu might have different default names, such as RTC_IRQHandler possible timer does't match ticker issue: external clock frequency definition error, check Clock Configuration,

• 17, start LoRaWAN code test now,

  add LoraWAN_Init(); after Board_Init(); add LoraWAN_Loop(); inside main while loop start debugging LORAWAN now!!! most common issues: interrupt level, rx windows mismatch with the tx for Class A

  finish