Diff: main.cpp

Revision:

7:164b5f80b483

Parent:

3:c92e21f305d8

--- a/main.cpp	Tue Jun 04 16:01:32 2013 +0100
+++ b/main.cpp	Tue Oct 14 06:43:12 2014 +0000
@@ -1,21 +1,137 @@
 #include "mbed.h"
 #include "rtos.h"
- 
-DigitalOut led1(LED1);
-DigitalOut led2(LED2);
- 
-void led2_thread(void const *args) {
-    while (true) {
-        led2 = !led2;
-        Thread::wait(1000);
+
+DigitalOut led1(P3_25);     //leds are inversed!
+DigitalOut led2(P3_26);     //leds are inversed!
+DigitalOut transmitter(P0_6);
+Timeout transmitterTimeOutControl;
+
+DigitalIn receiverIn(P0_5);
+int previousReceiverState = 0;
+Timer receiverTimer;
+
+#define RING_BUFFER_LENGTH 500
+
+#define PREAMBULA_MINIMUM_LENGTH 150
+#define PREAMBULA_MAXIMUM_LENGTH 200
+#define BIT_0_MINIMUM_LENGTH 27
+
+#define PACKET_LENGTH_IN_BITS 94
+
+unsigned short ringBuffer[RING_BUFFER_LENGTH];
+int ringBufferWriteIndex=0, ringBufferReadIndex=0;
+
+Serial pc(P0_2, P0_3);
+
+void parseAvcPacket(int fromRingIndex, int toRingIndex)
+{
+    int bitIndex = 0, blockStartLengthIndex = 0;
+    unsigned short blockBits = 0x0000;
+    for (int ringIndex = fromRingIndex; ringIndex != toRingIndex; )
+    {
+        int us_count = ringBuffer[ringBufferReadIndex];             
+        
+        if (us_count >= PREAMBULA_MAXIMUM_LENGTH)
+        {
+            pc.printf("\r\nWRONG %d us");
+            break;
+        }
+        else if (us_count >= PREAMBULA_MINIMUM_LENGTH)
+            pc.printf("\r\n");
+        else 
+        {
+            unsigned short bit = (us_count > BIT_0_MINIMUM_LENGTH) ? 0 : 1;
+            blockBits |= (bit << blockStartLengthIndex);
+                
+            int outInBlockLength = 8;//1, 4, 8, 12
+            if ((bitIndex == 0) || (bitIndex == 13) || (bitIndex == 26) || (bitIndex == 27) || (bitIndex == 32) || (bitIndex == 33) || 
+                (bitIndex == 42) || (bitIndex == 43) || (bitIndex == 52) || (bitIndex == 53) || (bitIndex == 62) || (bitIndex == 63) || 
+                (bitIndex == 72) || (bitIndex == 73) || (bitIndex == 82) || (bitIndex == 83) || (bitIndex == 92) || (bitIndex == 93))
+                 outInBlockLength = 1;
+            else if (((bitIndex < 13) && (bitIndex >= 1)) || ((bitIndex < 26) && (bitIndex >= 14)))
+                outInBlockLength = 12;
+            else if ((bitIndex < 32) && (bitIndex >= 28))
+                outInBlockLength = 4;
+            
+            if (blockStartLengthIndex >= outInBlockLength)
+            {
+                if (outInBlockLength == 1)
+                    pc.printf("%d ", blockBits);
+                else if (outInBlockLength == 4)
+                    pc.printf("%X ", blockBits);
+                else if (outInBlockLength == 8)
+                    pc.printf("%X ", blockBits);
+                else if (outInBlockLength == 12)
+                    pc.printf("%X ", blockBits);
+                    
+                blockStartLengthIndex = 0;
+                blockBits = 0x0000;
+            }
+
+            bitIndex ++;            
+            blockStartLengthIndex ++;
+        }
+            
+        ringIndex = (ringIndex+1) % RING_BUFFER_LENGTH;        
     }
 }
- 
-int main() {
-    Thread thread(led2_thread);
+
+void serialCommunicationThreadFunction(void const *args)
+{
+    pc.baud(115200);
+    pc.printf("\r\nAVC-Lan sniffer is ON\r\n\r\n");
     
-    while (true) {
-        led1 = !led1;
-        Thread::wait(500);
+    led1 = 1;
+
+    while (true) 
+    {
+        led1 = (ringBufferWriteIndex == ringBufferReadIndex);
+
+        int packetEndIndex = (ringBufferReadIndex+1) % RING_BUFFER_LENGTH;
+        int packetBitLength = 0;
+        for (; ringBufferWriteIndex != packetEndIndex; )
+            if ((packetBitLength == PACKET_LENGTH_IN_BITS) || ((ringBuffer[packetEndIndex] >= PREAMBULA_MINIMUM_LENGTH) && (ringBuffer[packetEndIndex] < PREAMBULA_MAXIMUM_LENGTH)))
+            {
+                parseAvcPacket(ringBufferReadIndex, (packetBitLength == PACKET_LENGTH_IN_BITS) ? packetEndIndex : (packetEndIndex-1));
+                break;
+            }
+            else
+            {
+                packetEndIndex = (packetEndIndex+1) % RING_BUFFER_LENGTH;
+                packetBitLength ++;
+            }
     }
 }
+
+int main()
+{
+    Thread serialCommunicationThread(serialCommunicationThreadFunction);
+
+    receiverIn.mode(PullUp);
+
+    receiverTimer.reset();
+    led2 = 1;
+
+    while (true) 
+    {
+        if (receiverIn != previousReceiverState)
+        {     
+            led2 = 0;
+            if (receiverIn)
+            {
+                receiverTimer.reset();
+                receiverTimer.start();
+            }
+            else
+            {
+                receiverTimer.stop();
+                int us_count = receiverTimer.read_us();                
+                ringBuffer[ringBufferWriteIndex] = us_count;
+                ringBufferWriteIndex = (ringBufferWriteIndex+1) % RING_BUFFER_LENGTH;
+            }
+                
+            previousReceiverState = receiverIn;
+            led2 = 1;
+        }
+    }
+}