[TagVal] Change serial number from integer to string

Author: vzahradnik

src/RemoteConnector.cpp

@@ -367,7 +367,7 @@ void TagValueRemoteConnector::encodeJoin() {
     char szName[40];
     safeProgCpy(szName, localInfoPgm->uuid, sizeof(szName));
     transport->writeField(FIELD_UUID, szName);
-    transport->writeFieldLong(FIELD_SERIAL_NO, (long)getBoardSerialNumber());
+    transport->writeField(FIELD_SERIAL_NO, getBoardSerialNumber());
     safeProgCpy(szName, localInfoPgm->name, sizeof(szName));
     transport->writeField(FIELD_MSG_NAME, szName);
     transport->writeFieldInt(FIELD_VERSION, API_VERSION);

src/tcUtil.cpp

@@ -19,13 +19,13 @@ char szGlobalBuffer[16];
 
 // if not defined give a developer one of one short of a billion
 #ifndef TC_BOARD_SERIAL_NO
-#define TC_BOARD_SERIAL_NO 999999999L
+#define TC_BOARD_SERIAL_NO "999999999"
 #endif //!TC_BOARD_SERIAL_NO
 
 // and implement the function
-const long glTcSerialNumber PROGMEM = TC_BOARD_SERIAL_NO;
-uint32_t getBoardSerialNumber() {
-    return pgm_read_dword(&glTcSerialNumber);
+const char glTcSerialNumber[] PROGMEM = TC_BOARD_SERIAL_NO;
+const char * getBoardSerialNumber() {
+    return reinterpret_cast<const char *>(glTcSerialNumber);
 }
 #endif // !TC_MANUAL_SERIAL_NO_IMPL
 
@@ -50,7 +50,7 @@ void showVersionDialog(const ConnectorLocalInfo *localInfo) {
         char sz[25];
         tccore::copyTcMenuVersion(sz, sizeof(sz));
         strncat(sz, " S/N:", sizeof(sz) - strlen(sz) - 1);
-        fastltoa(sz, (long)getBoardSerialNumber(), 9, NOT_PADDED, sizeof sz);
+        strncat(sz, getBoardSerialNumber(), sizeof(sz) - strlen(sz) - 1);
         dialog->copyIntoBuffer(sz);
     });
 }

src/tcUtil.h

@@ -31,14 +31,14 @@ struct ConnectorLocalInfo {
  * Provides the serial number for the board, it can be displayed and also used in remote JOIN messages to identify
  * the board uniquiely by UUID and serial number.
  *
- * If you want to use the default implementation you can define flag TC_BOARD_SERIAL_NO to a long int value that will
+ * If you want to use the default implementation you can define flag TC_BOARD_SERIAL_NO to a string literal that will
  * be stored as a constant in memory.
  *
  * If you want to have a custom implementation, define TC_MANUAL_SERIAL_NO_IMPL and then you must implement this method
  * yourself instead. This function should not take undue time if implemented by you as it could block networking.
  * @return the serial number
  */
-uint32_t getBoardSerialNumber();
+const char * getBoardSerialNumber();
 
 /**
  * Show the TcMenu version in a dialog that can be dismissed