diff --git a/arch/arm/include/lpc2378/irq.h b/arch/arm/include/lpc2378/irq.h
index 423159a533d09..bf60801f5d25d 100644
--- a/arch/arm/include/lpc2378/irq.h
+++ b/arch/arm/include/lpc2378/irq.h
@@ -119,10 +119,8 @@ extern "C"
 #define EXTERN extern
 #endif
 
-#ifndef CONFIG_VECTORED_INTERRUPTS
 void up_attach_vector(int irq, int priority, vic_vector_t handler);
 void up_detach_vector(int vector);
-#endif
 
 #undef EXTERN
 #ifdef __cplusplus
diff --git a/arch/arm/src/lpc2378/lpc2378.h b/arch/arm/src/lpc2378/lpc2378.h
index d9023e84fef15..f1495f6601f60 100644
--- a/arch/arm/src/lpc2378/lpc2378.h
+++ b/arch/arm/src/lpc2378/lpc2378.h
@@ -50,8 +50,6 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
-/* #define CONFIG_VECTORED_INTERRUPTS */
-
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/
diff --git a/arch/arm/src/lpc2378/lpc23xx_decodeirq.c b/arch/arm/src/lpc2378/lpc23xx_decodeirq.c
index c8c56e250ba41..47f2bbb496f79 100644
--- a/arch/arm/src/lpc2378/lpc23xx_decodeirq.c
+++ b/arch/arm/src/lpc2378/lpc23xx_decodeirq.c
@@ -84,11 +84,7 @@
  *
  ****************************************************************************/
 
-#ifndef CONFIG_VECTORED_INTERRUPTS
-uint32_t *arm_decodeirq(uint32_t *regs)
-#else
 static uint32_t *lpc23xx_decodeirq(uint32_t *regs)
-#endif
 {
   struct tcb_s *tcb = this_task();
 
@@ -144,22 +140,35 @@ static uint32_t *lpc23xx_decodeirq(uint32_t *regs)
 #endif
 }
 
-#ifdef CONFIG_VECTORED_INTERRUPTS
 uint32_t *arm_decodeirq(uint32_t *regs)
 {
-  vic_vector_t vector = (vic_vector_t) vic_getreg(VIC_ADDRESS_OFFSET);
+#ifdef CONFIG_SUPPRESS_INTERRUPTS
+  err("ERROR: Unexpected IRQ\n");
+  PANIC();
+#else
+
+  /* Check which IRQ fires */
 
-  /* Acknowledge the interrupt */
+  uint32_t irqbits = vic_getreg(VIC_IRQSTATUS_OFFSET) & 0xffffffff;
+  unsigned int irq;
 
-  arm_ack_irq(irq);
+  for (irq = 0; irq < NR_IRQS; irq++)
+    {
+      if (irqbits & (uint32_t) (1 << irq))
+        {
+          break;
+        }
+    }
 
-  /* Valid Interrupt */
+  /* Verify that the resulting IRQ number is valid */
 
-  if (vector != NULL)
+  if (irq < NR_IRQS)
     {
-      (vector)(regs);
+      /* Deliver the IRQ */
+
+      regs = arm_doirq(irq, regs);
     }
+#endif
 
-  return NULL;  /* Return not used in this architecture */
+  return regs;
 }
-#endif
diff --git a/arch/arm/src/lpc2378/lpc23xx_irq.c b/arch/arm/src/lpc2378/lpc23xx_irq.c
index 9b05374a4b4a0..1febde9c636e8 100644
--- a/arch/arm/src/lpc2378/lpc23xx_irq.c
+++ b/arch/arm/src/lpc2378/lpc23xx_irq.c
@@ -193,9 +193,7 @@ void arm_ack_irq(int irq)
   /* Clear interrupt */
 
   vic_putreg((1 << irq), VIC_SOFTINTCLEAR_OFFSET);
-#ifdef CONFIG_VECTORED_INTERRUPTS
   vic_putreg(0, VIC_ADDRESS_OFFSET);    /* dummy write to clear VICADDRESS */
-#endif
 }
 
 /****************************************************************************
@@ -230,7 +228,6 @@ int up_prioritize_irq(int irq, int priority)
  *
  ****************************************************************************/
 
-#ifndef CONFIG_VECTORED_INTERRUPTS
 void up_attach_vector(int irq, int vector, vic_vector_t handler)
 {
   /* Verify that the IRQ number and vector number are within range */
@@ -255,7 +252,6 @@ void up_attach_vector(int irq, int vector, vic_vector_t handler)
       leave_critical_section(flags);
     }
 }
-#endif
 
 /****************************************************************************
  * Name: up_detach_vector
@@ -265,7 +261,6 @@ void up_attach_vector(int irq, int vector, vic_vector_t handler)
  *
  ****************************************************************************/
 
-#ifdef CONFIG_VECTORED_INTERRUPTS
 void up_detach_vector(int vector)
 {
   /* Verify that the vector number is within range */
@@ -278,4 +273,3 @@ void up_detach_vector(int vector)
       vic_putreg(0, (VIC_VECTADDR0_OFFSET + offset));
     }
 }
-#endif
diff --git a/arch/arm/src/lpc2378/lpc23xx_timerisr.c b/arch/arm/src/lpc2378/lpc23xx_timerisr.c
index 46f04cfd9e618..23d3d0b65734c 100644
--- a/arch/arm/src/lpc2378/lpc23xx_timerisr.c
+++ b/arch/arm/src/lpc2378/lpc23xx_timerisr.c
@@ -91,11 +91,7 @@
  *
  ****************************************************************************/
 
-#ifdef CONFIG_VECTORED_INTERRUPTS
-static int lpc23xx_timerisr(uint32_t * regs)
-#else
 static int lpc23xx_timerisr(int irq, uint32_t * regs, void *arg)
-#endif
 {
   static uint32_t tick;
 
@@ -109,11 +105,9 @@ static int lpc23xx_timerisr(int irq, uint32_t * regs, void *arg)
 
   /* Reset the VIC as well */
 
-#ifdef CONFIG_VECTORED_INTERRUPTS
   /* write any value to VICAddress to acknowledge the interrupt */
 
   vic_putreg(0, VIC_ADDRESS_OFFSET);
-#endif
 
   if (tick++ > 100)
     {
@@ -186,11 +180,7 @@ void up_timer_initialize(void)
 
   /* Attach the timer interrupt vector */
 
-#ifdef CONFIG_VECTORED_INTERRUPTS
-  up_attach_vector(IRQ_SYSTIMER, ???, (vic_vector_t) lpc23xx_timerisr);
-#else
   irq_attach(IRQ_SYSTIMER, (xcpt_t)lpc23xx_timerisr, NULL);
-#endif
 
   /* And enable the system timer interrupt */