diff --git a/CVReader.ino b/CVReader.ino
index b64ef00..89e6b46 100644
--- a/CVReader.ino
+++ b/CVReader.ino
@@ -58,7 +58,7 @@ void loop() {
     } 
     else if (ch == '>') {
       buffer[bufferLength]='\0';
-      JMRIParser::parse(buffer);
+      JMRIParser::parse(Serial, buffer);
       inCommandPayload = false;
     } else if(inCommandPayload) {
       buffer[bufferLength++]= ch;
diff --git a/DIAG.cpp b/DIAG.cpp
deleted file mode 100644
index 580010f..0000000
--- a/DIAG.cpp
+++ /dev/null
@@ -1,27 +0,0 @@
-#include <arduino.h>
-#include <stdarg.h>
-
-void Serialprint(const __FlashStringHelper* input...) {
-  // thanks to Jan Turoň  https://arduino.stackexchange.com/questions/56517/formatting-strings-in-arduino-for-output
-
-  va_list args;
-  va_start(args, input);
-  char* flash=(char*)input;
-  for(int i=0; ; ++i) {
-    char c=pgm_read_byte_near(flash+i);
-    if (c=='\0') return;
-    if(c!='%') { Serial.print(c); continue; }
-    i++;
-    c=pgm_read_byte_near(flash+i);
-    switch(c) {
-      case '%': Serial.print('%'); break;
-      case 's': Serial.print(va_arg(args, char*)); break;
-      case 'd': Serial.print(va_arg(args, int), DEC); break;
-      case 'b': Serial.print(va_arg(args, int), BIN); break;
-      case 'o': Serial.print(va_arg(args, int), OCT); break;
-      case 'x': Serial.print(va_arg(args, int), HEX); break;
-      case 'f': Serial.print(va_arg(args, double), 2); break;
-    }
-  }
-  va_end(args);
-}
diff --git a/DIAG.h b/DIAG.h
index 8ac3fdd..76526a5 100644
--- a/DIAG.h
+++ b/DIAG.h
@@ -1,5 +1,5 @@
-void Serialprint(const __FlashStringHelper* input...);
+#include "StringParser.h"
 #ifndef DIAG_ENABLED
  #define DIAG_ENABLED true
 #endif
-#define DIAG if (DIAG_ENABLED) Serialprint
+#define DIAG if (DIAG_ENABLED) StringParser::print
diff --git a/JMRIParser.cpp b/JMRIParser.cpp
index 1ab6704..e78d2b6 100644
--- a/JMRIParser.cpp
+++ b/JMRIParser.cpp
@@ -2,7 +2,7 @@
 #include "JMRIParser.h"
 #include "DCC.h"
 #include "DCCWaveform.h"
-#include "DIAG.h"
+
 // This is a JMRI command parser
 // It doesnt know how the string got here, nor how it gets back.
 // It knows nothing about hardware or tracks... it just parses strings and
@@ -10,10 +10,10 @@
 //
 
 int JMRIParser::p[MAX_PARAMS];
-
+ 
 // See documentation on DCC class for info on this section
-void JMRIParser::parse(const char *com) {
-    DIAG(F("\nParsing %s\n"),com);
+void JMRIParser::parse(Stream  & stream,const char *com) {
+    StringParser::send(stream,F("\nParsing %s\n"),com);
     
     bool result;
     int params=StringParser::parse(com+1,p,MAX_PARAMS); 
@@ -24,7 +24,7 @@ void JMRIParser::parse(const char *com) {
 
     case 't':       // <t REGISTER CAB SPEED DIRECTION>
         DCC::setThrottle(p[1],p[2],p[3]);
-        DIAG(F("<T %d %d %d>"), p[0], p[2],p[3]);
+        StringParser::send(stream,F("<T %d %d %d>"), p[0], p[2],p[3]);
         break;
     
 /***** OPERATE ENGINE DECODER FUNCTIONS F0-F28 ****/
@@ -233,7 +233,7 @@ void JMRIParser::parse(const char *com) {
         */
         
         result=DCC::writeCVByte(p[0],p[1]);
-        DIAG(F("<r%d|%d|%d %d>"), p[2], p[3],p[0],result?p[1]:-1);
+        StringParser::send(stream,F("<r%d|%d|%d %d>"), p[2], p[3],p[0],result?p[1]:-1);
         break;
 
 /***** WRITE CONFIGURATION VARIABLE BIT TO ENGINE DECODER ON PROGRAMMING TRACK  ****/
@@ -253,7 +253,7 @@ void JMRIParser::parse(const char *com) {
         */
 
         result=DCC::writeCVBit(p[0],p[1],p[2]);
-        DIAG(F("<r%d|%d|%d %d %d>"), p[3],p[4], p[0],p[1],result?p[2]:-1);
+        StringParser::send(stream,F("<r%d|%d|%d %d %d>"), p[3],p[4], p[0],p[1],result?p[2]:-1);
         break;
 
 /***** READ CONFIGURATION VARIABLE BYTE FROM ENGINE DECODER ON PROGRAMMING TRACK  ****/
@@ -270,7 +270,7 @@ void JMRIParser::parse(const char *com) {
         *    where VALUE is a number from 0-255 as read from the requested CV, or -1 if read could not be verified
         */
        
-        DIAG(F("<r%d|%d|%d %d>"),p[1],p[2],p[0],DCC::readCV(p[0]));
+        StringParser::send(stream,F("<r%d|%d|%d %d>"),p[1],p[2],p[0],DCC::readCV(p[0]));
         break;
 
 /***** TURN ON POWER FROM MOTOR SHIELD TO TRACKS  ****/
@@ -283,7 +283,7 @@ void JMRIParser::parse(const char *com) {
         */
         DCCWaveform::mainTrack.setPowerMode(POWERMODE::ON);
         DCCWaveform::progTrack.setPowerMode(POWERMODE::ON);
-        DIAG(F("<p1>"));
+        StringParser::send(stream,F("<p1>"));
         break;
 
 /***** TURN OFF POWER FROM MOTOR SHIELD TO TRACKS  ****/
@@ -296,7 +296,7 @@ void JMRIParser::parse(const char *com) {
         */
         DCCWaveform::mainTrack.setPowerMode(POWERMODE::OFF);
         DCCWaveform::progTrack.setPowerMode(POWERMODE::OFF);
-        DIAG(F("<p0>"));
+        StringParser::send(stream,F("<p0>"));
         break;
 
 #ifdef THIS_IS_NOT_YET_COMPLETE    
@@ -309,7 +309,7 @@ void JMRIParser::parse(const char *com) {
         *    returns: <a CURRENT>
         *    where CURRENT = 0-1024, based on exponentially-smoothed weighting scheme
         */
-        DIAG(F("<a %d>"), DCCWaveform:mainTrack->getLastRead());
+        StringParser::send(stream,F("<a %d>"), DCCWaveform:mainTrack->getLastRead());
         break;
 
 /***** READ STATUS OF DCC++ BASE STATION  ****/
@@ -360,15 +360,15 @@ void JMRIParser::parse(const char *com) {
         CommManager::printf("<O>");
         break;
 #endif
-/***** PRINT CARRIAGE RETURN IN SERIAL MONITOR WINDOW  ****/
+/***** PRINT CARRIAGE RETURN IN stream MONITOR WINDOW  ****/
 
     case ' ':     // < >
         /*
-        *    simply prints a carriage return - useful when interacting with Ardiuno through serial monitor window
+        *    simply prints a carriage return - useful when interacting with Ardiuno through stream monitor window
         *
         *    returns: a carriage return
         */
-        DIAG(F("\n"));
+        StringParser::send(stream,F("\n"));
         break;
     }
 }
diff --git a/JMRIParser.h b/JMRIParser.h
index 53ce0e0..b1b7dc0 100644
--- a/JMRIParser.h
+++ b/JMRIParser.h
@@ -1,7 +1,7 @@
 
 struct JMRIParser
 {
-    static void parse(const char * command);
+    static void parse(Stream & stream,const char * command);
 
    private:
     static const int MAX_PARAMS=10; 
diff --git a/StringParser.cpp b/StringParser.cpp
index e6c9d3d..62881ac 100644
--- a/StringParser.cpp
+++ b/StringParser.cpp
@@ -1,4 +1,5 @@
 #include "StringParser.h"
+#include <stdarg.h>
 
 int StringParser::parse(const char * com, int result[], byte maxResults) {
   byte state=1;
@@ -42,3 +43,42 @@ int StringParser::parse(const char * com, int result[], byte maxResults) {
       }
       return parameterCount;
 }
+
+
+
+void StringParser::print( const __FlashStringHelper* input...) {
+  va_list args;
+  va_start(args, input);
+  send(Serial,input,args);
+}
+
+void StringParser::send(Stream & stream, const __FlashStringHelper* input...) {
+  va_list args;
+  va_start(args, input);
+  send(stream,input,args);
+}
+
+void StringParser::send(Stream & stream,const __FlashStringHelper* format, va_list args) {
+    
+
+  // thanks to Jan Turoň  https://arduino.stackexchange.com/questions/56517/formatting-strings-in-arduino-for-output
+
+  char* flash=(char*)format;
+  for(int i=0; ; ++i) {
+    char c=pgm_read_byte_near(flash+i);
+    if (c=='\0') return;
+    if(c!='%') { stream.print(c); continue; }
+    i++;
+    c=pgm_read_byte_near(flash+i);
+    switch(c) {
+      case '%': stream.print('%'); break;
+      case 's': stream.print(va_arg(args, char*)); break;
+      case 'd': stream.print(va_arg(args, int), DEC); break;
+      case 'b': stream.print(va_arg(args, int), BIN); break;
+      case 'o': stream.print(va_arg(args, int), OCT); break;
+      case 'x': stream.print(va_arg(args, int), HEX); break;
+      case 'f': stream.print(va_arg(args, double), 2); break;
+    }
+  }
+  va_end(args);
+}
diff --git a/StringParser.h b/StringParser.h
index 0286c4c..67c9cde 100644
--- a/StringParser.h
+++ b/StringParser.h
@@ -3,4 +3,9 @@ class StringParser
 {
   public:
     static int parse(const char * com, int result[], byte maxResults);
+    static void print( const __FlashStringHelper* input...);
+    static void send(Stream & serial, const __FlashStringHelper* input...);
+ private:
+    static void send(Stream & serial, const __FlashStringHelper* input,va_list args);
+
 };