diff --git a/BaS_gcc/Makefile b/BaS_gcc/Makefile
index b2272a7..817652b 100644
--- a/BaS_gcc/Makefile
+++ b/BaS_gcc/Makefile
@@ -41,7 +41,8 @@ CFLAGS=	-Wall \
 	-fomit-frame-pointer \
 	-ffreestanding \
 	-fleading-underscore \
-	-Wa,--register-prefix-optional
+	-Wa,--register-prefix-optional \
+	-g
 CFLAGS_OPTIMIZED = -mcpu=5474 \
 		-Wall \
 		-O2 \
diff --git a/BaS_gcc/sys/interrupts.c b/BaS_gcc/sys/interrupts.c
index 47d0bc0..3e1896d 100644
--- a/BaS_gcc/sys/interrupts.c
+++ b/BaS_gcc/sys/interrupts.c
@@ -37,7 +37,7 @@
 #include "dma.h"
 #include "pci.h"
 
-//#define IRQ_DEBUG
+// #define IRQ_DEBUG
 #if defined(IRQ_DEBUG)
 #define dbg(format, arg...) do { xprintf("DEBUG %s(): " format, __FUNCTION__, ##arg); } while (0)
 #else
@@ -247,20 +247,20 @@ bool pic_interrupt_handler(void *arg1, void *arg2)
 
     dbg("PIC interrupt\r\n");
 
-    rcv_byte = MCF_PSC3_PSCRB_8BIT;
+    rcv_byte = * (volatile uint8_t *) (&MCF_PSC3_PSCRB_8BIT);
     if (rcv_byte == 2)                  /* PIC requests RTC data */
     {
-        uint8_t *rtc_reg = (uint8_t *) 0xffff8961;
-        uint8_t *rtc_data = (uint8_t *) 0xffff8963;
+        volatile uint8_t *rtc_reg = (uint8_t *) 0xffff8961;
+        volatile uint8_t *rtc_data = (uint8_t *) 0xffff8963;
         int index = 0;
 
         err("PIC interrupt: requesting RTC data\r\n");
 
-        MCF_PSC3_PSCTB_8BIT = 0x82;     // header byte to PIC
+        * (volatile uint8_t *) (&MCF_PSC3_PSCTB_8BIT) = 0x82;     // header byte to PIC
         do
         {
             *rtc_reg = 0;
-            MCF_PSC3_PSCTB_8BIT = *rtc_data;
+            * (volatile uint8_t *) (&MCF_PSC3_PSCTB_8BIT) = *rtc_data;
         } while (index++ < 64);
     }
     return true;
diff --git a/BaS_gcc/sys/sysinit.c b/BaS_gcc/sys/sysinit.c
index 1153453..438b907 100644
--- a/BaS_gcc/sys/sysinit.c
+++ b/BaS_gcc/sys/sysinit.c
@@ -265,9 +265,6 @@ static void init_serial(void)
     MCF_PSC3_PSCCR = 0x05;
 #endif /* MACHINE_FIREBEE */
 
-    MCF_INTC_ICR32 = MCF_INTC_ICR_IL(7) |
-                     MCF_INTC_ICR_IL(4);      /* PSC3 interrupt vector. Do we need it? */
-
     xprintf("\r\nserial interfaces initialization: finished\r\n");
 }