From 2faa4b5d71303a4ec82607025379debccc7aa495 Mon Sep 17 00:00:00 2001
From: jgromes <jan.gromes@gmail.com>
Date: Sat, 28 May 2022 17:57:42 +0200
Subject: [PATCH] [Morse] Use out of band tone for space in AFSK mode (#529)

---
 src/protocols/AFSK/AFSK.cpp   | 6 +++++-
 src/protocols/AFSK/AFSK.h     | 4 +++-
 src/protocols/Morse/Morse.cpp | 2 +-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/protocols/AFSK/AFSK.cpp b/src/protocols/AFSK/AFSK.cpp
index 53ffe7d9..29c00448 100644
--- a/src/protocols/AFSK/AFSK.cpp
+++ b/src/protocols/AFSK/AFSK.cpp
@@ -24,9 +24,13 @@ int16_t AFSKClient::tone(uint16_t freq, bool autoStart) {
   return(RADIOLIB_ERR_NONE);
 }
 
-int16_t AFSKClient::noTone() {
+int16_t AFSKClient::noTone(bool keepOn) {
   Module* mod = _phy->getMod();
   mod->noTone(_pin);
+  if(keepOn) {
+    return(0);
+  }
+
   return(_phy->standby());
 }
 
diff --git a/src/protocols/AFSK/AFSK.h b/src/protocols/AFSK/AFSK.h
index 9df3cb41..72b45471 100644
--- a/src/protocols/AFSK/AFSK.h
+++ b/src/protocols/AFSK/AFSK.h
@@ -46,9 +46,11 @@ class AFSKClient  {
     /*!
       \brief Stops transmitting audio tone.
 
+      \param freq Keep transmitter on - this may limit noise when switching transmitter on or off.
+
       \returns \ref status_codes
     */
-    int16_t noTone();
+    int16_t noTone(bool keepOn = false);
 
 #if !defined(RADIOLIB_GODMODE)
   private:
diff --git a/src/protocols/Morse/Morse.cpp b/src/protocols/Morse/Morse.cpp
index 2395562e..d3dd40f6 100644
--- a/src/protocols/Morse/Morse.cpp
+++ b/src/protocols/Morse/Morse.cpp
@@ -308,7 +308,7 @@ int16_t MorseClient::transmitDirect(uint32_t freq, uint32_t freqHz) {
 int16_t MorseClient::standby() {
   #if !defined(RADIOLIB_EXCLUDE_AFSK)
   if(_audio != nullptr) {
-    return(_audio->noTone());
+    return(_audio->noTone(true));
   }
   #endif
   return(_phy->standby());