[RTTY] Added support for ITA2 print and println

examples/SX127x_RTTY_Transmit/SX127x_RTTY_Transmit.ino

@@ -97,13 +97,18 @@ void loop() {
     // RTTY client must be configured to 5 bits
     rtty.begin(434, 183, 45, 5);
 
+    // synd synchronization string ("RYRY..." corresponds
+    // to binary 01010101010101010101...)
+    ITA2 sync = "RYRYRYRY";
+    rtty.println(sync);
+
     // create ITA2-encoded string
     // NOTE: ASCII characters that do not have ITA2
     //       equivalent will be replaced with NUL
-    ITA2 itaStr = "HELLO WORLD\n";
-
-    // send the ITA2 string
-    rtty.write(itaStr.byteArr(), itaStr.length());  
+    ITA2 itaStr = "HELLO WORLD";
+    
+    // print the ITA2 string
+    rtty.println(itaStr);
   */
   
   // turn transmitter off

src/protocols/RTTY.cpp

@@ -124,6 +124,10 @@ size_t RTTYClient::write(uint8_t b) {
   return(1);
 }
 
+size_t RTTYClient::print(ITA2& ita2) {
+  return(RTTYClient::write(ita2.byteArr(), ita2.length()));
+}
+
 size_t RTTYClient::print(const String& str) {
   return(RTTYClient::write((uint8_t*)str.c_str(), str.length()));
 }
@@ -176,7 +180,22 @@ size_t RTTYClient::print(double n, int digits) {
 }
 
 size_t RTTYClient::println(void) {
-  return(RTTYClient::write("\r\n"));
+  size_t n = 0;
+  if(_dataBits == 5) {
+    // use ITA2 line
+    ITA2 lf = "\r\n";
+    n = RTTYClient::print(lf);
+  } else {
+    // use ASCII line
+    n = RTTYClient::write("\r\n");
+  }
+  return(n);
+}
+
+size_t RTTYClient::println(ITA2& ita2) {
+  size_t n = RTTYClient::print(ita2);
+  n += RTTYClient::println();
+  return(n);
 }
 
 size_t RTTYClient::println(const String& str) {

src/protocols/RTTY.h

@@ -42,6 +42,7 @@ class RTTYClient {
     size_t write(uint8_t* buff, size_t len);
     size_t write(uint8_t b);
     
+    size_t print(ITA2 &);
     size_t print(const String &);
     size_t print(const char[]);
     size_t print(char);
@@ -53,6 +54,7 @@ class RTTYClient {
     size_t print(double, int = 2);
     
     size_t println(void);
+    size_t println(ITA2 &);
     size_t println(const String &s);
     size_t println(const char[]);
     size_t println(char);