updated serial system

ringbuffer.h

@@ -18,14 +18,15 @@
 
 #include <stdint.h>
 
-template < int BUFFER_SIZE >
+template < int BUFFER_SIZE, typename T = uint8_t >
 class RingBuffer
 {
 private:
     
-    uint_fast16_t _headIndex = 0;
-    uint_fast16_t _tailIndex = 0;
-    uint8_t _buffer[BUFFER_SIZE];
+    volatile uint_fast16_t _headIndex = 0;
+    volatile uint_fast16_t _tailIndex = 0;
+	volatile bool          _overrun = false;
+    volatile T _buffer[BUFFER_SIZE];
     
 public:
     
@@ -34,22 +35,29 @@ public:
         flush();
     }
     
-    uint_fast16_t remaining()
+    uint_fast16_t remaining() const volatile
     {
         return (_headIndex-_tailIndex);
     }
     
-    bool isOverun(uint_fast16_t margin = 0)
+    uint_fast16_t remainingCapacity() const volatile
     {
-       return remaining() >= BUFFER_SIZE - margin;
+        return BUFFER_SIZE - (_headIndex-_tailIndex);
     }
     
-    bool isEmpty()
+    bool isOverun() volatile
+    {
+	   bool returnVal = _overrun;
+	   _overrun = false;
+       return returnVal;
+    }
+    
+    bool isEmpty() const volatile
     {
         return _tailIndex >= _headIndex;
     }
     
-    uint8_t read()
+    T read() volatile
     {
         if(!isEmpty())
         {
@@ -59,7 +67,7 @@ public:
         else return '\0';
     }
     
-    unsigned int read( uint8_t* buffer, unsigned int length )
+    unsigned int read( T* buffer, unsigned int length ) volatile
     {
         unsigned int i = 0;
         for(; i < length && !isEmpty(); i++)
@@ -69,7 +77,7 @@ public:
         return i;
     }
     
-    void write( uint8_t in )
+    void write( T in ) volatile
     {
         if (_headIndex - BUFFER_SIZE > 0 && _tailIndex - BUFFER_SIZE > 0)
         {
@@ -78,21 +86,26 @@ public:
         }
         _buffer[_headIndex % BUFFER_SIZE] = in;
         _headIndex++;
+		if(remaining() > BUFFER_SIZE) 
+		{
+			_overrun = true;
+			_tailIndex = _headIndex - BUFFER_SIZE;
+		}
     }
     
-    void write( uint8_t* buffer, unsigned int length )
+    void write( T* buffer, const unsigned int length ) volatile
     {
-        for(uint8_t i = 0; i < length; i++) write(buffer[i]);
+        for(unsigned int i = 0; i < length; i++) write(buffer[i]);
     }
     
-    void flush()
+    void flush(T flushCharacter = ' ') volatile
     {
         _headIndex = 0;
         _tailIndex = 0;
-        for(int i = 0; i < BUFFER_SIZE; i++) _buffer[i] = ' ';
+        for(int i = 0; i < BUFFER_SIZE; i++) _buffer[i] = flushCharacter;
     }
     
-    unsigned int getString(uint8_t terminator, char* buffer, const unsigned int bufferLength)
+    unsigned int getString(T terminator, T* buffer, const unsigned int bufferLength) volatile
     {
         unsigned int i = 0;
         for(; i <= remaining() && i <= BUFFER_SIZE && _buffer[(_tailIndex+i) % BUFFER_SIZE] != terminator; i++);
@@ -100,7 +113,7 @@ public:
         if( i < remaining() && i > 0)
         {
             if(i > bufferLength-1) i = bufferLength-1;
-            read((uint8_t*)buffer, i);
+            read(buffer, i);
             buffer[i]='\0';
             _tailIndex++;
         }

serial.cpp

@@ -1,19 +1,19 @@
 #include "serial.h"
 #include "ringbuffer.h"
 
-RingBuffer<SERIAL_BUFFER_SIZE> rxBuffer;
+volatile RingBuffer<SERIAL_BUFFER_SIZE, volatile uint8_t> rxBuffer;
 
 bool stopped = false;
 
-ISR (USART_RX_vect) //I have seen worse interrupt sintax
+ISR(USART_RX_vect) //I have seen worse interrupt sintax
 {
 	rxBuffer.write(UDR0);
-        if(serialFlowControl && !stopped && rxBuffer.isOverun(32))
-        {
-            loop_until_bit_is_set(UCSR0A, UDRE0);
-            UDR0 = 0x13;
-            stopped = true;
-        }
+	if(serialFlowControl && !stopped && rxBuffer.remainingCapacity() < 32)
+	{
+		loop_until_bit_is_set(UCSR0A, UDRE0);
+		UDR0 = 0x13;
+		stopped = true;
+	}
 }
 
 Serial::Serial() 
@@ -23,6 +23,7 @@ Serial::Serial()
     UCSR0C = _BV(UCSZ01) | _BV(UCSZ00); 
     UCSR0B = _BV(RXEN0) | _BV(TXEN0);   //Enable RX and TX
     UCSR0B |= (1 << RXCIE0); //Enable Rx interuppt
+	sei();
 }
 
 void Serial::putChar(const char c)
@@ -98,7 +99,7 @@ char Serial::getChar()
 {
     if(!rxBuffer.isEmpty())
     {
-        if(serialFlowControl && stopped && !rxBuffer.isOverun(32))
+        if(serialFlowControl && stopped && rxBuffer.remainingCapacity() > 32 )
         {
             loop_until_bit_is_set(UCSR0A, UDRE0);
             UDR0 = 0x11;
@@ -111,7 +112,7 @@ char Serial::getChar()
 
 unsigned int Serial::getString(char* buffer, const int bufferLength)
 {
-    return rxBuffer.getString(_terminator, buffer, bufferLength);
+    return rxBuffer.getString(_terminator, (uint8_t*)buffer, bufferLength);
 }
 
 unsigned int Serial::read(char* buffer, const unsigned int length )

serial.h

@@ -2,7 +2,7 @@
 #define SERIAL_H
 
 #define BAUD 38400
-#define SERIAL_BUFFER_SIZE 128
+#define SERIAL_BUFFER_SIZE 256
 
 #include <util/setbaud.h>
 #include <avr/io.h>