Index: flash_start_gcc.s
===================================================================
--- /YC3121_demo/Librarier/startup/flash_start_gcc.s	(revision 735)
+++ /YC3121_demo/Librarier/startup/flash_start_gcc.s	(working copy)
@@ -10,23 +10,26 @@
 		.thumb_func
 		
 hard_fault_handler:
-		bl HARD_FAULT_IRQHandler
-		b isr_ret
+		ldr r0,=HARD_FAULT_IRQHandler       
+		bx r0
+		nop
 		.thumb_func
 		
 svc_handler:
-		bl SVC_IRQHandler
-		b isr_ret
+		ldr r0,=SVC_IRQHandler
+		bx r0
+		nop
 		.thumb_func
 
 pendsv_handler:
-		bl PENDSV_IRQHandler
-		b isr_ret
+		ldr r0,=PENDSV_IRQHandler
+		bx r0
+		nop
 		.thumb_func
 systick:
-		bl SYSTICK_IRQHandler
-		b isr_ret
-		
+		ldr r0,=SYSTICK_IRQHandler
+		bx r0
+		nop
 		.thumb_func
 irq0: 		
 		mov r0,#4*0
@@ -161,11 +164,7 @@
 		ldr r1,=isr_table
 		ldr r0,[r0, r1]
 		bx r0
-isr_ret:
-		mov r0,#0
-		sub r0,#7
-		mov lr,r0
-		bx lr
+