diff --git a/DCCEXParser.cpp b/DCCEXParser.cpp
index cbb152e..221d8b0 100644
--- a/DCCEXParser.cpp
+++ b/DCCEXParser.cpp
@@ -190,9 +190,9 @@ void DCCEXParser::setAtCommandCallback(AT_COMMAND_CALLBACK callback)
 // Parse an F() string 
 void DCCEXParser::parse(const FSH * cmd) {
       DIAG(F("SETUP(\"%S\")"),cmd);
-      int size=strlen_P((char *)cmd)+1; 
+      int size=STRLEN_P((char *)cmd)+1; 
       char buffer[size];
-      strcpy_P(buffer,(char *)cmd);
+      STRCPY_P(buffer,(char *)cmd);
       parse(&USB_SERIAL,(byte *)buffer,NULL);
 }
 
diff --git a/FSH.h b/FSH.h
index f4bf47e..d031935 100644
--- a/FSH.h
+++ b/FSH.h
@@ -47,7 +47,11 @@
 typedef __FlashStringHelper FSH;
 #define FLASH PROGMEM
 #define GETFLASH(addr) pgm_read_byte_near(addr)
-
+#define STRCPY_P strcpy_P
+#define STRCMP_P strcmp_P
+#define STRNCPY_P strncpy_P
+#define STRNCMP_P strncmp_P
+#define STRLEN_P strlen_P
 
 #if defined(ARDUINO_AVR_MEGA) || defined(ARDUINO_AVR_MEGA2560)
 // AVR_MEGA memory deliberately placed at end of link may need _far functions
@@ -80,5 +84,10 @@ typedef char FSH;
 #define GETFLASH(addr) (*(const byte *)(addr))
 #define GETHIGHFLASH(data,offset)  (*(const byte *)(GETFARPTR(data)+offset))
 #define GETHIGHFLASHW(data,offset) (*(const uint16_t *)(GETFARPTR(data)+offset))
+#define STRCPY_P strcpy
+#define STRCMP_P strcmp
+#define STRNCPY_P strncpy
+#define STRNCMP_P strncmp
+#define STRLEN_P strlen
 #endif
 #endif
diff --git a/RingStream.cpp b/RingStream.cpp
index 9377a0a..12dbaa1 100644
--- a/RingStream.cpp
+++ b/RingStream.cpp
@@ -83,7 +83,7 @@ size_t RingStream::printFlash(const FSH * flashBuffer) {
 
 // Establish the actual length of the progmem string.
 char * flash=(char *)flashBuffer;
-int16_t plength=strlen_P(flash);
+int16_t plength=STRLEN_P(flash);
 if (plength==0) return 0; // just ignore empty string
 
 // Retain the buffer count as it will be modified by the marker+address insert
diff --git a/WifiInterface.cpp b/WifiInterface.cpp
index bdc8dad..f69cc2f 100644
--- a/WifiInterface.cpp
+++ b/WifiInterface.cpp
@@ -184,8 +184,8 @@ wifiSerialState WifiInterface::setup2(const FSH* SSid, const FSH* password,
   checkForOK(1000, true);                       // Not always OK, sometimes "no change"
 
   const char *yourNetwork = "Your network ";
-  if (strncmp_P(yourNetwork, (const char*)SSid, 13) == 0 || strncmp_P("", (const char*)SSid, 13) == 0) {
-    if (strncmp_P(yourNetwork, (const char*)password, 13) == 0) {
+  if (STRNCMP_P(yourNetwork, (const char*)SSid, 13) == 0 || STRNCMP_P("", (const char*)SSid, 13) == 0) {
+    if (STRNCMP_P(yourNetwork, (const char*)password, 13) == 0) {
       // If the source code looks unconfigured, check if the
       // ESP8266 is preconfigured in station mode.
       // We check the first 13 chars of the SSid and the password
@@ -258,7 +258,7 @@ wifiSerialState WifiInterface::setup2(const FSH* SSid, const FSH* password,
   
     i=0;
     do {
-      if (strncmp_P(yourNetwork, (const char*)password, 13) == 0) {
+      if (STRNCMP_P(yourNetwork, (const char*)password, 13) == 0) {
 	// unconfigured
         StringFormatter::send(wifiStream, F("AT+CWSAP%s=\"DCCEX_%s\",\"PASS_%s\",%d,4\r\n"),
                                           oldCmd ? "" : "_CUR", macTail, macTail, channel);