diff --git a/BaS_gcc/include/bas_utils.h b/BaS_gcc/include/bas_utils.h
index a0fe0d2..ae3499e 100644
--- a/BaS_gcc/include/bas_utils.h
+++ b/BaS_gcc/include/bas_utils.h
@@ -26,4 +26,7 @@
 #define CLEAR_BIT(p,bit)        p &= ~(bit)
 #define CLEAR_BIT_NO(p,nr)      CLEAR_BIT(p, (1 << (nr)))
 
+extern void write_pic_byte(uint8_t value);
+extern uint8_t read_pic_byte(void);
+
 #endif /* _BAS_UTILS_H_ */
diff --git a/BaS_gcc/sys/BaS.c b/BaS_gcc/sys/BaS.c
index 4e6aaaa..ef1947d 100644
--- a/BaS_gcc/sys/BaS.c
+++ b/BaS_gcc/sys/BaS.c
@@ -31,6 +31,7 @@
 #include "bas_printf.h"
 #include "bas_string.h"
 #include "bas_types.h"
+#include "bas_utils.h"
 #include "sd_card.h"
 #include "wait.h"
 
diff --git a/BaS_gcc/sys/interrupts.c b/BaS_gcc/sys/interrupts.c
index 464e47e..531cc56 100644
--- a/BaS_gcc/sys/interrupts.c
+++ b/BaS_gcc/sys/interrupts.c
@@ -61,8 +61,6 @@ struct isrentry
 
 static struct isrentry isrtab[MAX_ISR_ENTRY];      /* list of interrupt service routines */
 
-extern void write_pic_byte(uint8_t value);
-extern uint8_t read_pic_byte(void);
 
 /*
  * clear the table of interrupt service handlers