diff --git a/c64/,,config_generic.s b/c64/,,config_generic.s
index cba2e0d3..48da55c3 100644
--- a/c64/,,config_generic.s
+++ b/c64/,,config_generic.s
@@ -42,6 +42,7 @@
 
 #define CONFIG_IEC
 #define CONFIG_IEC_BLANK_SCREEN
+// #define CONFIG_IEC_DOLPHINDOS  // please keep disabled for now  
 #define CONFIG_IEC_JIFFYDOS
 // #define CONFIG_TAPE_NORMAL     // please keep disabled for now
 #define CONFIG_TAPE_TURBO
diff --git a/c64/,,config_mega65.s b/c64/,,config_mega65.s
index b2087518..61bf255f 100644
--- a/c64/,,config_mega65.s
+++ b/c64/,,config_mega65.s
@@ -44,6 +44,7 @@
 
 #define CONFIG_IEC
 #define CONFIG_IEC_BLANK_SCREEN
+// #define CONFIG_IEC_DOLPHINDOS  // please keep disabled for now  
 #define CONFIG_IEC_JIFFYDOS
 // #define CONFIG_TAPE_NORMAL     // please keep disabled for now
 // #define CONFIG_TAPE_TURBO
diff --git a/c64/,,config_testing.s b/c64/,,config_testing.s
index 19376b5a..a70ff39e 100644
--- a/c64/,,config_testing.s
+++ b/c64/,,config_testing.s
@@ -43,6 +43,7 @@
 
 #define CONFIG_IEC
 // #define CONFIG_IEC_BLANK_SCREEN
+// #define CONFIG_IEC_DOLPHINDOS  // please keep disabled for now  
 #define CONFIG_IEC_JIFFYDOS
 // #define CONFIG_TAPE_NORMAL     // please keep disabled for now
 #define CONFIG_TAPE_TURBO
diff --git a/c64/,,config_ultimate64.s b/c64/,,config_ultimate64.s
index 1856fd44..22089550 100644
--- a/c64/,,config_ultimate64.s
+++ b/c64/,,config_ultimate64.s
@@ -42,6 +42,7 @@
 
 #define CONFIG_IEC
 #define CONFIG_IEC_BLANK_SCREEN
+// #define CONFIG_IEC_DOLPHINDOS  // please keep disabled for now  
 #define CONFIG_IEC_JIFFYDOS
 // #define CONFIG_TAPE_NORMAL     // please keep disabled for now
 #define CONFIG_TAPE_TURBO
diff --git a/c64/kernal/iec_fast/dolphindos_detect.s b/c64/kernal/iec_fast/dolphindos_detect.s
new file mode 100644
index 00000000..ef135e8d
--- /dev/null
+++ b/c64/kernal/iec_fast/dolphindos_detect.s
@@ -0,0 +1,26 @@
+
+//
+// Helper routine for JiffyDOS detection
+//
+
+// The standard parallel cable (used by SpeedDOS, DolphinDOS 2, etc.) connects the following UserPort lines:
+// - PB0-PB7    - CIA2_PRB ($DD01), CIA #2 port B
+// - PC2, FLAG2 - CIA2_ICR ($DD0D), CIA #2 handshaking line
+//
+// See:
+// - http://sta.c64.org/cbmpar41c.html
+// - http://sta.c64.org/cbmpar71c.html
+// - Commodore 64 Programers Referencee Guide, pages 360-361, 429
+// - Computes Mapping the C64, page 183
+
+
+
+#if CONFIG_IEC_DOLPHINDOS
+
+
+dolphindos_detect:
+
+	panic #$00
+
+
+#endif // CONFIG_IEC_DOLPHINDOS