[Morse] Merge pull request #96 from IU5HKU/master

Reorganized morsecode symbols array and updated the MorseClient::writ…

examples/Morse/Morse_Transmit/Morse_Transmit.ino

@@ -104,7 +104,7 @@ void loop() {
 
   // floating point number
   // NOTE: When using println(), the transmission will be
-  //       terminated with cross signal (.-.-.).
+  //       terminated with end-of-work signal (...-.-).
   float f = -3.1415;
   morse.println(f, 3);
 

src/protocols/Morse/Morse.cpp

@@ -1,73 +1,5 @@
 #include "Morse.h"
 
-// structure to save data about character Morse code
-/*!
-  \cond RADIOLIB_DOXYGEN_HIDDEN
-*/
-struct Morse_t {
-  char c;                                             // ASCII character
-  char m[7];                                          // Morse code representation
-};
-/*!
-  \endcond
-*/
-
-// array of all Morse code characters
-const Morse_t MorseTable[MORSE_LENGTH] PROGMEM = {
-  {'A', ".-"},
-  {'B',"-..."},
-  {'C', "-.-."},
-  {'D',"-.."},
-  {'E',"."},
-  {'F',"..-."},
-  {'G',"--."},
-  {'H',"...."},
-  {'I',".."},
-  {'J',".---"},
-  {'K',"-.-"},
-  {'L',".-.."},
-  {'M',"--"},
-  {'N',"-."},
-  {'O',"---"},
-  {'P',".--."},
-  {'Q',"--.-"},
-  {'R',".-."},
-  {'S',"..."},
-  {'T',"-"},
-  {'U',"..-"},
-  {'V',"...-"},
-  {'W',".--"},
-  {'X',"-..-"},
-  {'Y',"-.--"},
-  {'Z',"--.."},
-  {'1',".----"},
-  {'2',"..---"},
-  {'3',"...--"},
-  {'4',"....-"},
-  {'5',"....."},
-  {'6',"-...."},
-  {'7',"--..."},
-  {'8',"---.."},
-  {'9',"----."},
-  {'0',"-----"},
-  {'.',".-.-.-"},
-  {',',"--..--"},
-  {':',"---..."},
-  {'?',"..--.."},
-  {'\'',".----."},
-  {'-',"-....-"},
-  {'/',"-..-."},
-  {'(',"-.--."},
-  {')',"-.--.-"},
-  {'\"',".-..-."},
-  {'=',"-...-"},
-  {'+',".-.-."},
-  {'@',".--.-."},
-  {' ',"_"},                               // space is used to separate words
-  {0x01,"-.-.-"},                          // ASCII SOH (start of heading) is used as alias for start signal
-  {0x02,".-.-."}                           // ASCII EOT (end of transmission) is used as alias for stop signal
-};
-
 MorseClient::MorseClient(PhysicalLayer* phy) {
   _phy = phy;
 }
@@ -86,7 +18,7 @@ int16_t MorseClient::begin(float base, uint8_t speed) {
 }
 
 size_t MorseClient::startSignal() {
-  return(MorseClient::write(0x01));
+  return(MorseClient::write('_'));
 }
 
 size_t MorseClient::write(const char* str) {
@@ -106,52 +38,55 @@ size_t MorseClient::write(uint8_t* buff, size_t len) {
 }
 
 size_t MorseClient::write(uint8_t b) {
-  // find the correct Morse code in array
+  // check unprintable ASCII characters and boundaries
-  Morse_t mc;
+  if((b < ' ') || (b == 0x60) || (b > 'z')) {
-  bool found = false;
+    return(0);
-  for(uint8_t pos = 0; pos < MORSE_LENGTH; pos++) {
-    memcpy_P(&mc, &MorseTable[pos], sizeof(Morse_t));
-    if(mc.c == toupper(b)) {
-      found = true;
-      break;
-    }
   }
 
-  // check if the requested code was found in the array
+  // inter-word pause (space)
-  if(found) {
+  if(b == ' ') {
-    RADIOLIB_DEBUG_PRINT(mc.c);
+    RADIOLIB_DEBUG_PRINTLN(F("space"));
-    RADIOLIB_DEBUG_PRINT('\t');
+    _phy->standby();
-    RADIOLIB_DEBUG_PRINTLN(mc.m);
+    delay(4 * _dotLength);
+    return(1);
+  }
 
-    // iterate over Morse code representation and output appropriate tones
+  // get morse code from lookup table
-    for(uint8_t i = 0; i < strlen(mc.m); i++) {
+  uint8_t code = pgm_read_byte(&MorseTable[(uint8_t)(toupper(b) - 32)]);
-      switch(mc.m[i]) {
+
-        case '.':
+  // check unsupported characters
+  if(code == MORSE_UNSUPORTED) {
+    return(0);
+  }
+
+  // iterate through codeword until guard bit is reached
+  while(code > MORSE_GUARDBIT) {
+
+    // send dot or dash
+    if (code & MORSE_DASH) {
+      RADIOLIB_DEBUG_PRINT('-');
+      _phy->transmitDirect(_base);
+      delay(3 * _dotLength);
+    } else {
+      RADIOLIB_DEBUG_PRINT('.');
       _phy->transmitDirect(_base);
       delay(_dotLength);
-          break;
-        case '-':
-          _phy->transmitDirect(_base);
-          delay(_dotLength * 3);
-          break;
-        case '_':
-          // do nothing (word space)
-          break;
     }
 
     // symbol space
     _phy->standby();
     delay(_dotLength);
+
+    // move onto the next bit
+    code >>= 1;
   }
 
   // letter space
+  _phy->standby();
+  delay(2 * _dotLength);
   RADIOLIB_DEBUG_PRINTLN();
-    delay(_dotLength * 3);
 
   return(1);
-  }
-
-  return(0);
 }
 
 size_t MorseClient::print(__FlashStringHelper* fstr) {
@@ -219,7 +154,7 @@ size_t MorseClient::print(double n, int digits) {
 }
 
 size_t MorseClient::println(void) {
-  return(MorseClient::write(0x02));
+  return(MorseClient::write('^'));
 }
 
 size_t MorseClient::println(__FlashStringHelper* fstr) {

src/protocols/Morse/Morse.h

@@ -4,7 +4,81 @@
 #include "../../TypeDef.h"
 #include "../PhysicalLayer/PhysicalLayer.h"
 
-#define MORSE_LENGTH                                  52
+#define MORSE_DOT                                     0b0
+#define MORSE_DASH                                    0b1
+#define MORSE_GUARDBIT                                0b1
+#define MORSE_UNSUPORTED                              0xFF
+
+// Morse character table: - using codes defined in ITU-R M.1677-1
+//                        - Morse code representation is saved LSb first, using additional bit as guard
+//                        - position in array corresponds ASCII code minus MORSE_ASCII_OFFSET
+//                        - ASCII characters marked MORSE_UNSUPORTED do not have ITU-R M.1677-1 equivalent
+static const uint8_t MorseTable[] PROGMEM = {
+    0b00,                   // space
+    0b110101,               // ! (unsupported)
+    0b1010010,              // "
+    MORSE_UNSUPORTED,       // # (unsupported)
+    MORSE_UNSUPORTED,       // $ (unsupported)
+    MORSE_UNSUPORTED,       // % (unsupported)
+    MORSE_UNSUPORTED,       // & (unsupported)
+    0b1011110,              // '
+    0b101101,               // (
+    0b1101101,              // )
+    MORSE_UNSUPORTED,       // * (unsupported)
+    0b101010,               // +
+    0b1110011,              // ,
+    0b1100001,              // -
+    0b1101010,              // .
+    0b101001,               // /
+    0b111111,               // 0
+    0b111110,               // 1
+    0b111100,               // 2
+    0b111000,               // 3
+    0b110000,               // 4
+    0b100000,               // 5
+    0b100001,               // 6
+    0b100011,               // 7
+    0b100111,               // 8
+    0b101111,               // 9
+    0b1000111,              // :
+    MORSE_UNSUPORTED,       // ; (unsupported)
+    MORSE_UNSUPORTED,       // < (unsupported)
+    0b110001,               // =
+    MORSE_UNSUPORTED,       // > (unsupported)
+    0b1001100,              // ?
+    0b1010110,              // @
+    0b110,                  // A
+    0b10001,                // B
+    0b10101,                // C
+    0b1001,                 // D
+    0b10,                   // E
+    0b10100,                // F
+    0b1011,                 // G
+    0b10000,                // H
+    0b100,                  // I
+    0b11110,                // J
+    0b1101,                 // K
+    0b10010,                // L
+    0b111,                  // M
+    0b101,                  // N
+    0b1111,                 // O
+    0b10110,                // P
+    0b11011,                // Q
+    0b1010,                 // R
+    0b1000,                 // S
+    0b11,                   // T
+    0b1100,                 // U
+    0b11000,                // V
+    0b1110,                 // W
+    0b11001,                // X
+    0b11101,                // Y
+    0b10011,                // Z
+    MORSE_UNSUPORTED,       // [ (unsupported)
+    MORSE_UNSUPORTED,       // \ (unsupported)
+    MORSE_UNSUPORTED,       // ] (unsupported)
+    0b1101000,              // ^ (unsupported, used as alias for end of work)
+    0b110101                // _ (unsupported, used as alias for starting signal)
+};
 
 /*!
   \class MorseClient