loracomm.c

/* ===================================================================== *
 *                             LORA HANDLING                             *
 * ===================================================================== */
 
#include "stm32f439xx.h"
 
#include "FreeRTOS.h"
#include "event_groups.h"
#include "message_buffer.h"
 
#include "groups.h"
#include "loracomm.h"
#include "stateupdate.h"
 
#include "devicelist.h"
#include "devices.h"
 
#include "gpiopin.h"
 
#include "a3g4250d.h"
#include "kx134_1211.h"
#include "sx1272.h"
 
#include "packets.h"
 
extern EventGroupHandle_t xMsgReadyGroup;
extern MessageBufferHandle_t xLoRaTxBuff;
extern EventGroupHandle_t xSystemStatusGroup;

void vLoRaTransmit(void *argument) {
  const TickType_t blockTime = portMAX_DELAY;
  uint8_t rxData[LORA_MSG_LENGTH];
 
  SX1272_t *lora     = DeviceList_getDeviceHandle(DEVICE_LORA).device;
  GPIOpin_t rfToggle = GPIOpin_init(GPIOE, GPIO_PIN2, NULL);
 
  for (;;) {
    // Wait for SX1272 to be ready for transmission
    EventBits_t uxBits = xEventGroupWaitBits(xMsgReadyGroup, GROUP_MESSAGE_READY_LORA, pdFALSE, pdFALSE, blockTime);
    if ((uxBits & GROUP_MESSAGE_READY_LORA)) {
      // Wait to receive message in buffer
      size_t xReceivedBytes = xMessageBufferReceive(
          xLoRaTxBuff,
          (void *)rxData,
          sizeof(rxData),
          blockTime
      );
      // Transmit if message is available
      if (xReceivedBytes) {
        rfToggle.reset(&rfToggle); // Toggle RF front-end for transmit
        lora->transmit(lora, rxData);
        xEventGroupClearBits(xMsgReadyGroup, GROUP_MESSAGE_READY_LORA);
      }
    }
  }
}

void vLoRaSample(void *argument) {
  const TickType_t xFrequency = pdMS_TO_TICKS(250);
  const TickType_t blockTime  = pdMS_TO_TICKS(125);
 
  A3G4250D_t *gyro            = DeviceList_getDeviceHandle(DEVICE_GYRO).device;
  KX134_1211_t *lAccel        = DeviceList_getDeviceHandle(DEVICE_ACCEL_LOW).device;
  KX134_1211_t *hAccel        = DeviceList_getDeviceHandle(DEVICE_ACCEL_HIGH).device;
 
  enum State *flightState     = StateHandle_getHandle("FlightState").state;
  float *altitude             = StateHandle_getHandle("Altitude").state;
  float *velocity             = StateHandle_getHandle("Velocity").state;
 
  for (;;) {
    // Block until 250ms interval
    TickType_t xLastWakeTime = xTaskGetTickCount();
    vTaskDelayUntil(&xLastWakeTime, xFrequency);
 
    uint8_t systemStatus = xEventGroupGetBits(xSystemStatusGroup);
 
    // Create AVData packet with current data
    SX1272_Packet avData = SX1272_AVData(
        LORA_HEADER_AV_DATA,
        *flightState | systemStatus,
        lAccel->rawAccelData,
        hAccel->rawAccelData,
        KX134_1211_DATA_TOTAL,
        gyro->rawGyroData,
        A3G4250D_DATA_TOTAL,
        *altitude,
        *velocity
    );
 
    // Add packet to queue
    xMessageBufferSend(xLoRaTxBuff, &avData, LORA_MSG_LENGTH, blockTime);
  }
}

void EXTI1_IRQHandler(void) {
  BaseType_t xHigherPriorityTaskWoken = pdFALSE, xResult;
 
  // Clear pending interrupt
  EXTI->PR |= (0x02);
 
  // Let the transmit task know it can continue
  xResult = xEventGroupSetBitsFromISR(
      xMsgReadyGroup,
      GROUP_MESSAGE_READY_LORA,
      &xHigherPriorityTaskWoken
  );
 
  if (xResult != pdFAIL)
    portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
}