Added GSC functionality (#56)

Author: Penguronik

Drivers/common/drivers_config/inc/drivers_config.hpp

@@ -17,4 +17,6 @@ extern SBUSReceiver* sbus_pointer;
 extern UARTDevice* pRFD900;
 extern CircularBuffer *rfd900_circular_buffer;
 
+#define RFD900_BUF_SIZE 11200 // 40 * 280(max Mavlink message size)
+
 #endif

Drivers/common/drivers_config/src/drivers_config.cpp

@@ -9,7 +9,6 @@ SBUSReceiver* sbus_pointer = &sbus_instance;
 /*
     creating RFD900 instance
 */
-const uint8_t RFD900_BUF_SIZE = 280;
 uint8_t rfd900_buf[RFD900_BUF_SIZE];
 CircularBuffer rfd900_circular_buffer_inst(rfd900_buf, RFD900_BUF_SIZE);
 

TelemetryManager/Inc/GroundStationCommunication.hpp

@@ -25,6 +25,9 @@
  * implementation.
  */
 class GroundStationCommunication {
+   private:
+    uint8_t internalBuffer_[RFD900_BUF_SIZE];
+
    public:
     /**
      * @brief Construct a new Ground Station Communication object. Do whatever needs to be done
@@ -37,14 +40,7 @@ class GroundStationCommunication {
     GroundStationCommunication(TMCircularBuffer& DMAReceiveBuffer, uint8_t* lowPriorityTransmitBuffer, uint8_t* highPriorityTransmitBuffer, int length);
     ~GroundStationCommunication();
 
-
-    /**
-     * To make c++ happy while using rfd900_circular_buffer from drivers_config.hpp, we need to
-     * create a pointer to the buffer. Then we dereference it.
-     */
-    // TMCircularBuffer* DMAReceiveBufferPtr = new TMCircularBuffer(rfd900_circular_buffer);
-
-/*
+    /*
      * When the DMA interrupt is triggered the data should be stored in the DMAReceiveBuffer
      * IF there is space.
      */
@@ -69,13 +65,6 @@ class GroundStationCommunication {
      * to the ground station
      */
     void transmit(TMCircularBuffer& transmissionBuffer);
-
-    /**
-     * @brief This is the Interrupt Service Routine (ISR) for when the RFD 900 receives data from
-     * the ground station and stores bytes from the transmission into the GSC.DMAReceiveBuffer if
-     * there is space. Otherwise the data is discarded.
-     */
-    void receiveInterruptServiceRoutine();
 };
 
 #endif  // GROUNDSTATIONCOMMS_H

TelemetryManager/Inc/TMCircularBuffer.hpp

@@ -56,10 +56,10 @@ class TMCircularBuffer : public CircularBuffer {
     bool enqueue(MAVLinkByte byte);
 
     /**
-     * @brief Get the index of the last full message in the queue determined by the end flag
-     * in the MAVLink message. This is so if we have a partial message in the queue because
-     * an ISR was triggered while we were in the middle of enqueuing a message, we
-     * only send completed messages and keep the partial message to be finished after the ISR.
+     * @brief Get the number of bytes until the end of the last full message in the queue
+     * determined by the end flag in the MAVLink message. This is so if we have a partial message 
+     * in the queue because an ISR was triggered while we were in the middle of enqueuing a message, 
+     * we only send completed messages and keep the partial message to be finished after the ISR.
      * These partial messages once filled will be sent during the next transmission.
      *
      * @return int The index of the last full message in the queue determined by the end flag

TelemetryManager/Src/GroundStationCommunication.cpp

@@ -22,24 +22,18 @@ GroundStationCommunication::~GroundStationCommunication() {
 
 void GroundStationCommunication::transmit(TMCircularBuffer &transmissionBuffer) {
     // START: Send the bytes in transmissionBuffer to the ground station via RFD900
+    int bytesToTransmit = transmissionBuffer.bytesUntilLastMessageEnd();
+    
+    if (bytesToTransmit > RFD900_BUF_SIZE) {
+        bytesToTransmit = RFD900_BUF_SIZE;
+    }
+
+    for (int i {0}; i < bytesToTransmit; ++i) {
+        internalBuffer_[i] = transmissionBuffer.dequeue();
+    }
+    pRFD900->transmit(internalBuffer_, bytesToTransmit);
 
     // END: Send the bytes in transmissionBuffer to the ground station via RFD900
 
     return;
 }
-
-void GroundStationCommunication::receiveInterruptServiceRoutine() {
-    int bytesReceived = 0;  // replace with actual number of bytes received
-
-    // if GSC.DMAReceiveBuffer has enough space for the new data add it
-    // otherwise discard the data
-    if (DMAReceiveBuffer.remainingMemory() > bytesReceived) {
-        // add the new data to GSC.DMAReceiveBuffer
-    } else {
-        // discard the new data
-        // not a great way to handle this, but it's a start
-    }
-
-    // end of ISR
-    return;
-}