Toggle SoftwareSerial interrupts when starting / stopping to listen

This prevents interrupts from triggering when the SoftwareSerial
instance is not even listening.

Additionally, this removes the need to disable interrupts in
SoftwareSerial::listen, since no interrupts are active while it touches
the variables.

1 files changed, 6 insertions, 4 deletions

diff --git a/libraries/SoftwareSerial/SoftwareSerial.cpp b/libraries/SoftwareSerial/SoftwareSerial.cpp
index a429f7d..b98451f 100644
--- a/libraries/SoftwareSerial/SoftwareSerial.cpp
+++ b/libraries/SoftwareSerial/SoftwareSerial.cpp
@@ -183,12 +183,14 @@ bool SoftwareSerial::listen()
 

   if (active_object != this)

   {

+    if (active_object)

+      active_object->stopListening();

+

     _buffer_overflow = false;

-    uint8_t oldSREG = SREG;

-    cli();

     _receive_buffer_head = _receive_buffer_tail = 0;

     active_object = this;

-    SREG = oldSREG;

+

+    setRxIntMsk(true);

     return true;

   }

 

@@ -200,6 +202,7 @@ bool SoftwareSerial::stopListening()
 {

   if (active_object == this)

   {

+    setRxIntMsk(false);

     active_object = NULL;

     return true;

   }

@@ -418,7 +421,6 @@ void SoftwareSerial::begin(long speed)
     // (others might also need it, so we disable the interrupt by using

     // the per-pin PCMSK register).

     *digitalPinToPCICR(_receivePin) |= _BV(digitalPinToPCICRbit(_receivePin));

-    setRxIntMsk(true);

     tunedDelay(_tx_delay); // if we were low this establishes the end

   }