Made library header only again and provided way to disable interrupt vectors

hardware1.hpp

@@ -1,4 +1,5 @@
-#pragma once
+#ifndef UART_HARDWARE_1_HPP
+#define UART_HARDWARE_1_HPP
 
 #include <stdint.h>
 
@@ -118,3 +119,40 @@ class Hardware1<cfg, Driven::INTERRUPT, mode>
 } // namespace uart
 
 #undef FORCE_INLINE
+
+#endif
+
+//////////////////////////////////////////////////////////////////////////
+
+#ifdef UART1_INT_VECTORS
+
+#include <avr/interrupt.h>
+
+namespace uart {
+namespace detail {
+
+#if defined(__AVR_ATmega1284P__)
+
+void (*fnRx1IntHandler)() = nullptr;
+void (*fnDataReg1EmptyIntHandler)() = nullptr;
+
+ISR(USART1_RX_vect)
+{
+	if (fnRx1IntHandler)
+		fnRx1IntHandler();
+}
+
+ISR(USART1_UDRE_vect)
+{
+	if (fnDataReg1EmptyIntHandler)
+		fnDataReg1EmptyIntHandler();
+}
+
+#endif
+
+} // namespace detail
+} // namespace uart
+
+#undef UART1_INT_VECTORS
+
+#endif