speed up forwarding of packets

Author: Vuurvos1

code/controller/src/main.cpp

@@ -112,14 +112,15 @@ void loop()
   static unsigned long lastSend = 0;
   if (millis() - lastSend > 2000)
   {
+    // data
     std::vector<uint8_t> data = {
         static_cast<uint8_t>(random(65)),
         static_cast<uint8_t>(random(65)),
         static_cast<uint8_t>(random(65)),
         static_cast<uint8_t>(random(65)),
         static_cast<uint8_t>(random(65))};
 
-    std::vector<uint8_t> packet = createPacket(data);
+    auto packet = createPacket(data);
 
     // print the packet
     Serial.print("Packet: ");

code/module/src/main.cpp

@@ -10,6 +10,13 @@ HardwareSerial mySerial(2);
 
 // Buffer for serial data
 std::vector<uint8_t> serialBuffer;
+bool readingPacket = false;
+
+void handleMyByte(uint8_t byte)
+{
+  Serial.println("Received byte: " + String(byte));
+  // TODO: set the flap number
+}
 
 void setup()
 {
@@ -24,44 +31,24 @@ void loop()
   // Check if data is available to read
   if (mySerial.available())
   {
-    // Resize vector to available bytes
-    serialBuffer.resize(mySerial.available());
-    int bytesRead = mySerial.readBytes(serialBuffer.data(), serialBuffer.size());
-    Serial.print("Received ");
-    Serial.print(bytesRead);
-    Serial.println(" bytes");
+    uint8_t incomming = mySerial.read();
 
-    // print as hex
-    Serial.print("Data: ");
-    for (int i = 0; i < bytesRead; i++)
+    if (!readingPacket && incomming != END_BYTE)
     {
-      Serial.print("0x");
-      Serial.print(serialBuffer[i], HEX);
-      Serial.print(" ");
+      readingPacket = true;
+      handleMyByte(incomming);
     }
-    Serial.println();
-
-    // validate the packet
-    if (!validatePacket(serialBuffer))
+    else
     {
-      Serial.println("Invalid packet");
-      return;
+      // forward the data
+      Serial.print(String(incomming) + " ");
+      mySerial.write(incomming);
     }
 
-    // get first byte
-    uint8_t command = serialBuffer[1];
-    Serial.print("Command: ");
-    Serial.println(command);
-
-    // create packet to forward from remaining bytes
-    auto forwardPacket = createForwardPacket(serialBuffer);
-    if (forwardPacket.size() <= 3)
+    if (incomming == END_BYTE)
     {
-      Serial.println("Forward packet is too small");
-      return;
+      Serial.println("End of packet");
+      readingPacket = false;
     }
-
-    // forward the data
-    mySerial.write(forwardPacket.data(), forwardPacket.size());
   }
 }

code/shared/include/utils.h

@@ -2,8 +2,8 @@
 
 #include <vector>
 
-#define START_BYTE 0xAA // 10101010 in binary
-#define END_BYTE 0x55   // 01010101 in binary
+// #define START_BYTE 0xAA // 10101010 in binary
+#define END_BYTE 0xFF // 01010101 in binary
 
 uint8_t calculateCRC(uint8_t *data, uint8_t length)
 {
@@ -17,26 +17,19 @@ uint8_t calculateCRC(uint8_t *data, uint8_t length)
 
 /**
  * create a packet
- * [START][DATA...][CRC][END]
+ * [DATA...][END]
  */
 std::vector<uint8_t> createPacket(const std::vector<uint8_t> &data)
 {
-  std::vector<uint8_t> packet(data.size() + 3);
-  packet[0] = START_BYTE;
-  std::copy(data.begin(), data.end(), packet.begin() + 1);
-  packet[data.size() + 1] = calculateCRC(const_cast<uint8_t *>(data.data()), data.size());
-  packet[data.size() + 2] = END_BYTE;
+  std::vector<uint8_t> packet(data.size() + 1);        // +1 for END byte only
+  std::copy(data.begin(), data.end(), packet.begin()); // Copy data at the start
+  packet[data.size()] = END_BYTE;                      // Add END_BYTE at the end
   return packet;
 }
 
 bool validatePacket(const std::vector<uint8_t> &packet)
 {
-  if (packet.size() < 3)
-  {
-    return false;
-  }
-
-  if (packet[0] != START_BYTE)
+  if (packet.size() < 2)
   {
     return false;
   }
@@ -46,16 +39,6 @@ bool validatePacket(const std::vector<uint8_t> &packet)
     return false;
   }
 
-  // Extract data portion and verify CRC
-  std::vector<uint8_t> data(packet.begin() + 1, packet.end() - 2);
-  uint8_t receivedCRC = packet[packet.size() - 2];
-  uint8_t calculatedCRC = calculateCRC(const_cast<uint8_t *>(data.data()), data.size());
-
-  if (receivedCRC != calculatedCRC)
-  {
-    return false;
-  }
-
   return true;
 }
 
@@ -64,6 +47,6 @@ bool validatePacket(const std::vector<uint8_t> &packet)
  */
 std::vector<uint8_t> createForwardPacket(const std::vector<uint8_t> &packet)
 {
-  std::vector<uint8_t> data(packet.begin() + 2, packet.end() - 2); // skip START byte and first data byte, and skip CRC and END bytes
+  std::vector<uint8_t> data(packet.begin() + 1, packet.end() - 1);
   return createPacket(data);
 }

code/test/utils_test.cpp

@@ -27,39 +27,26 @@ void test_createPacket_function(void)
   std::vector<uint8_t> packet = createPacket(data);
 
   uint8_t length = data.size();
-  // Check START_BYTE
-  TEST_ASSERT_EQUAL(START_BYTE, packet[0]);
 
   // Check data
   for (size_t i = 0; i < length; i++)
   {
-    TEST_ASSERT_EQUAL(data[i], packet[i + 1]);
+    TEST_ASSERT_EQUAL(data[i], packet[i]);
   }
 
-  // Check CRC (0x01 ^ 0x02 ^ 0x03 ^ 0x04 ^ 0x05 = 0x01)
-  TEST_ASSERT_EQUAL(0x01, packet[length + 1]);
-
   // Check END_BYTE
-  TEST_ASSERT_EQUAL(END_BYTE, packet[length + 2]);
+  TEST_ASSERT_EQUAL(packet[length], END_BYTE);
 }
 
 void test_validatePacket_function(void)
 {
   // valid packet
-  std::vector<uint8_t> packet = {0xAA, 0x01, 0x02, 0x03, 0x04, 0x05, 0x01, 0x55};
+  std::vector<uint8_t> packet = {0xAA, 0x01, 0x02, 0x03, 0x04, 0x05, 0x01, 0xFF};
   TEST_ASSERT_TRUE(validatePacket(packet));
 
-  // invalid crc
-  std::vector<uint8_t> packet2 = {0xAA, 0x01, 0x02, 0x03, 0x04, 0x05, 0x02, 0x55};
-  TEST_ASSERT_FALSE(validatePacket(packet2));
-
-  // missing start byte
-  std::vector<uint8_t> packet3 = {0x01, 0x02, 0x03, 0x04, 0x05, 0x01, 0x55};
-  TEST_ASSERT_FALSE(validatePacket(packet3));
-
   // missing end byte
-  std::vector<uint8_t> packet4 = {0xAA, 0x01, 0x02, 0x03, 0x04, 0x05, 0x01};
-  TEST_ASSERT_FALSE(validatePacket(packet4));
+  std::vector<uint8_t> packet2 = {0x01, 0x02, 0x03, 0x04, 0x05, 0x01};
+  TEST_ASSERT_FALSE(validatePacket(packet2));
 }
 
 void test_createForwardPacket_function(void)
@@ -68,8 +55,8 @@ void test_createForwardPacket_function(void)
   std::vector<uint8_t> forwardPacket = createForwardPacket(packet);
   TEST_ASSERT_EQUAL(packet.size() - 1, forwardPacket.size());
 
-  TEST_ASSERT_EQUAL(forwardPacket[1], 0x02);
-  TEST_ASSERT_EQUAL(forwardPacket[2], 0x03);
+  TEST_ASSERT_EQUAL(forwardPacket[0], 0x02);
+  TEST_ASSERT_EQUAL(forwardPacket[1], 0x03);
 }
 
 int main(int argc, char **argv)