diff --git a/wiringPi/wiringPi.c b/wiringPi/wiringPi.c
index 90dfece..6f66c76 100644
--- a/wiringPi/wiringPi.c
+++ b/wiringPi/wiringPi.c
@@ -4533,7 +4533,7 @@ int wiringPiISR (int pin, int mode, void (*function)(void))
     else
       modeS = "both" ;
 
-    sprintf (pinS, "%d", pin) ;
+    sprintf (pinS, "%d", bcmGpioPin);
 
     if ((pid = fork ()) < 0)	// Fail
       return wiringPiFailure (WPI_FATAL, "wiringPiISR: fork failed: %s\n", strerror (errno)) ;