diff --git a/bsp/lpc176x/board.c b/bsp/lpc176x/board.c
index beed89b890168eb7e0045de7e5f4167f004705a7..a5cb4b030e700131590945246a67dfd40dff61f4 100644
--- a/bsp/lpc176x/board.c
+++ b/bsp/lpc176x/board.c
@@ -42,6 +42,11 @@ void rt_hw_timer_handler(void)
 	rt_interrupt_leave();
 }
 
+void SysTick_Handler(void)
+{
+    rt_hw_timer_handler();
+}
+
 /**
  * This function will initial LPC17xx board.
  */
diff --git a/bsp/lpc176x/emac.c b/bsp/lpc176x/emac.c
index 5f82cf76a4ea8ac122c52c568ab1a06329cff8d3..bcdb61fc600899b4845a130254aa742655bcbea9 100644
--- a/bsp/lpc176x/emac.c
+++ b/bsp/lpc176x/emac.c
@@ -19,7 +19,8 @@ struct lpc17xx_emac
 	rt_uint8_t  dev_addr[MAX_ADDR_LEN];		/* hw address	*/
 };
 static struct lpc17xx_emac lpc17xx_emac_device;
-static struct rt_semaphore sem_slot, sem_lock;
+static struct rt_semaphore sem_lock;
+static struct rt_event tx_event;
 
 /* Local Function Prototypes */
 static void write_PHY (rt_uint32_t PhyReg, rt_uint32_t Value);
@@ -32,11 +33,8 @@ void ENET_IRQHandler(void)
     /* enter interrupt */
     rt_interrupt_enter();
 
-	status = LPC_EMAC->IntStatus & LPC_EMAC->IntEnable;
+	status = LPC_EMAC->IntStatus;
 
-	/* Clear the interrupt. */ 
-	LPC_EMAC->IntClear = status; 
- 
 	if (status & INT_RX_DONE)
 	{
 		/* Disable EMAC RxDone interrupts. */
@@ -47,10 +45,23 @@ void ENET_IRQHandler(void)
 	}
 	else if (status & INT_TX_DONE)
 	{
-		/* release one slot */
-		rt_sem_release(&sem_slot);
+		/* set event */
+		rt_event_send(&tx_event, 0x01);
+	}
+
+	if (status & INT_RX_OVERRUN)
+	{
+		rt_kprintf("rx overrun\n");
 	}
 
+	if (status & INT_TX_UNDERRUN)
+	{
+		rt_kprintf("tx underrun\n");
+	}
+
+	/* Clear the interrupt. */ 
+	LPC_EMAC->IntClear = status; 
+ 
     /* leave interrupt */
     rt_interrupt_leave();
 }
@@ -344,8 +355,22 @@ rt_err_t lpc17xx_emac_tx( rt_device_t dev, struct pbuf* p)
 	struct pbuf *q;
 	rt_uint8_t *ptr;
 
-	/* take a slot */
-	rt_sem_take(&sem_slot, RT_WAITING_FOREVER);
+	/* calculate next index */
+	IndexNext = LPC_EMAC->TxProduceIndex + 1;
+	if(IndexNext > LPC_EMAC->TxDescriptorNumber) IndexNext = 0;
+
+	/* check whether block is full */
+	while (IndexNext == LPC_EMAC->TxConsumeIndex)
+	{
+		rt_err_t result;
+		rt_uint32_t recved;
+		
+		/* there is no block yet, wait a flag */
+		result = rt_event_recv(&tx_event, 0x01, 
+			RT_EVENT_FLAG_AND | RT_EVENT_FLAG_CLEAR, RT_WAITING_FOREVER, &recved);
+
+		RT_ASSERT(result == RT_EOK);
+	}
 
 	/* lock EMAC device */
 	rt_sem_take(&sem_lock, RT_WAITING_FOREVER);
@@ -435,19 +460,20 @@ struct pbuf *lpc17xx_emac_rx(rt_device_t dev)
 
 void lpc17xx_emac_hw_init(void)
 {
-	rt_sem_init(&sem_slot, "tx_slot", NUM_TX_FRAG, RT_IPC_FLAG_FIFO);
+	rt_event_init(&tx_event, "tx_event", RT_IPC_FLAG_FIFO);
 	rt_sem_init(&sem_lock, "eth_lock", 1, RT_IPC_FLAG_FIFO);
 
 	/* set autonegotiation mode */
 	lpc17xx_emac_device.phy_mode = EMAC_PHY_AUTO;
 
+	// OUI 00-60-37 NXP Semiconductors
+	lpc17xx_emac_device.dev_addr[0] = 0x00;
+	lpc17xx_emac_device.dev_addr[1] = 0x60;
+	lpc17xx_emac_device.dev_addr[2] = 0x37;
 	/* set mac address: (only for test) */
-	lpc17xx_emac_device.dev_addr[0] = 0x1E;
-	lpc17xx_emac_device.dev_addr[1] = 0x30;
-	lpc17xx_emac_device.dev_addr[2] = 0x6C;
-	lpc17xx_emac_device.dev_addr[3] = 0xA2;
-	lpc17xx_emac_device.dev_addr[4] = 0x45;
-	lpc17xx_emac_device.dev_addr[5] = 0x5E;
+	lpc17xx_emac_device.dev_addr[3] = 0x12;
+	lpc17xx_emac_device.dev_addr[4] = 0x34;
+	lpc17xx_emac_device.dev_addr[5] = 0x56;
 
 	lpc17xx_emac_device.parent.parent.init		= lpc17xx_emac_init;
 	lpc17xx_emac_device.parent.parent.open		= lpc17xx_emac_open;