1 files changed, 5 insertions, 9 deletions
diff --git a/libraries/SoftwareSerial/SoftwareSerial.cpp b/libraries/SoftwareSerial/SoftwareSerial.cpp
index 527f3f9..0a16ff7 100644
--- a/libraries/SoftwareSerial/SoftwareSerial.cpp
+++ b/libraries/SoftwareSerial/SoftwareSerial.cpp
@@ -57,9 +57,9 @@ volatile uint8_t SoftwareSerial::_receive_buffer_head = 0;
 //
 // This function generates a brief pulse
 // for debugging or measuring on an oscilloscope.
+#if _DEBUG
 inline void DebugPulse(uint8_t pin, uint8_t count)
 {
-#if _DEBUG
   volatile uint8_t *pport = portOutputRegister(digitalPinToPort(pin));
 
   uint8_t val = *pport;
@@ -68,8 +68,10 @@ inline void DebugPulse(uint8_t pin, uint8_t count)
     *pport = val | digitalPinToBitMask(pin);
     *pport = val;
   }
-#endif
 }
+#else
+inline void DebugPulse(uint8_t, uint8_t) {}
+#endif
 
 //
 // Private methods
@@ -467,13 +469,7 @@ size_t SoftwareSerial::write(uint8_t b)
 
 void SoftwareSerial::flush()
 {
-  if (!isListening())
-    return;
-
-  uint8_t oldSREG = SREG;
-  cli();
-  _receive_buffer_head = _receive_buffer_tail = 0;
-  SREG = oldSREG;
+  // There is no tx buffering, simply return
 }
 
 int SoftwareSerial::peek()