diff --git a/bsp/avr32uc3b0/application.c b/bsp/avr32uc3b0/application.c
new file mode 100644
index 000000000..db7ad39d4
--- /dev/null
+++ b/bsp/avr32uc3b0/application.c
@@ -0,0 +1,76 @@
+/*
+ * File      : application.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2010-03-30     Kyle         First version
+ */
+
+#include <rtthread.h>
+#include "compiler.h"
+#include "gpio.h"
+
+char thread_led1_stack[1024];
+struct rt_thread thread_led1;
+static void rt_thread_entry_led1(void* parameter)
+{
+    while (1)
+    {
+        /* led on */
+        rt_kprintf("LED1 on\r\n");
+        gpio_tgl_gpio_pin(AVR32_PIN_PA08);
+        rt_thread_delay(50); /* sleep 0.5 second and switch to other thread */
+
+        /* led off */
+        rt_kprintf("LED1 off\r\n");
+        gpio_tgl_gpio_pin(AVR32_PIN_PA08);
+        rt_thread_delay(50);
+    }
+}
+
+char thread_led2_stack[1024];
+struct rt_thread thread_led2;
+void rt_thread_entry_led2(void* parameter)
+{
+    while (1)
+    {
+        /* led on */
+        rt_kprintf("LED2 on, count = %d\r\n", count);
+        gpio_tgl_gpio_pin(AVR32_PIN_PA07);
+        rt_thread_delay(RT_TICK_PER_SECOND);
+
+        /* led off */
+        rt_kprintf("LED2 off\r\n");
+        gpio_tgl_gpio_pin(AVR32_PIN_PA07);
+        rt_thread_delay(RT_TICK_PER_SECOND);
+    }
+}
+
+int rt_application_init()
+{
+    /* create led1 thread */
+    rt_thread_init(&thread_led1,
+				   "led1",
+                   rt_thread_entry_led1,
+                   RT_NULL,
+                   &thread_led1_stack[0],
+                   sizeof(thread_led1_stack), 5, 5);
+    rt_thread_startup(&thread_led1);
+
+    //------- init led2 thread
+    rt_thread_init(&thread_led2,
+                   "led2",
+                   rt_thread_entry_led2,
+                   RT_NULL,
+                   &thread_led2_stack[0],
+                   sizeof(thread_led2_stack),5,10);
+    rt_thread_startup(&thread_led2);
+
+    return 0;
+}
diff --git a/bsp/avr32uc3b0/avr32elf_uc3b0256.lds b/bsp/avr32uc3b0/avr32elf_uc3b0256.lds
new file mode 100644
index 000000000..3f4ff5705
--- /dev/null
+++ b/bsp/avr32uc3b0/avr32elf_uc3b0256.lds
@@ -0,0 +1,211 @@
+/* Default linker script, for normal executables */
+OUTPUT_FORMAT("elf32-avr32", "elf32-avr32",
+	      "elf32-avr32")
+OUTPUT_ARCH(avr32:uc)
+ENTRY(_start)
+SEARCH_DIR("/home/mingwbuild/mingwavr32/avr32/lib");
+/* Do we need any of these for elf?
+   __DYNAMIC = 0;    */
+MEMORY
+{
+    FLASH (rxai!w) : ORIGIN = 0x80000000, LENGTH = 256K
+    CPUSRAM (wxa!ri) : ORIGIN = 0x00000004, LENGTH = 0x7FFC
+    USERPAGE : ORIGIN = 0x80800000, LENGTH = 512
+    FACTORYPAGE : ORIGIN = 0x80800200, LENGTH = 512
+}
+SECTIONS
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+  .init           :
+  {
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+  .text           :
+  {
+    *(.text .stub .text.* .gnu.linkonce.t.*)
+    KEEP (*(.text.*personality*))
+    /* .gnu.warning sections are handled specially by elf32.em.  */
+    *(.gnu.warning)
+    /* section information for finsh shell */
+    . = ALIGN(4);
+    __fsymtab_start = .;
+    KEEP(*(FSymTab))
+    __fsymtab_end = .;
+    . = ALIGN(4);
+    __vsymtab_start = .;
+    KEEP(*(VSymTab))
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+  .fini           :
+  {
+    KEEP (*(.fini))
+  } >FLASH AT>FLASH =0xd703d703
+  PROVIDE (__etext = .);
+  PROVIDE (_etext = .);
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+  .eh_frame       : ONLY_IF_RO { KEEP (*(.eh_frame)) } >FLASH AT>FLASH
+  .gcc_except_table   : ONLY_IF_RO { KEEP (*(.gcc_except_table)) *(.gcc_except_table.*) } >FLASH AT>FLASH
+  .dalign	: { . = ALIGN(8); PROVIDE(_data_lma = .); } >FLASH AT>FLASH
+  PROVIDE (_data = ORIGIN(CPUSRAM));
+  . = ORIGIN(CPUSRAM);
+  /* Exception handling  */
+  .eh_frame       : ONLY_IF_RW { KEEP (*(.eh_frame)) } >CPUSRAM AT>FLASH
+  .gcc_except_table   : ONLY_IF_RW { KEEP (*(.gcc_except_table)) *(.gcc_except_table.*) } >CPUSRAM AT>FLASH
+  /* Thread Local Storage sections  */
+  .tdata	  : { *(.tdata .tdata.* .gnu.linkonce.td.*) } >CPUSRAM AT>FLASH
+  .tbss		  : { *(.tbss .tbss.* .gnu.linkonce.tb.*) *(.tcommon) } >CPUSRAM
+  /* Ensure the __preinit_array_start label is properly aligned.  We
+     could instead move the label definition inside the section, but
+     the linker would then create the section even if it turns out to
+     be empty, which isn't pretty.  */
+  PROVIDE (__preinit_array_start = ALIGN(32 / 8));
+  .preinit_array     : { KEEP (*(.preinit_array)) } >CPUSRAM AT>FLASH
+  PROVIDE (__preinit_array_end = .);
+  PROVIDE (__init_array_start = .);
+  .init_array     : { KEEP (*(.init_array)) } >CPUSRAM AT>FLASH
+  PROVIDE (__init_array_end = .);
+  PROVIDE (__fini_array_start = .);
+  .fini_array     : { KEEP (*(.fini_array)) } >CPUSRAM AT>FLASH
+  PROVIDE (__fini_array_end = .);
+  .ctors          :
+  {
+    /* gcc uses crtbegin.o to find the start of
+       the constructors, so we make sure it is
+       first.  Because this is a wildcard, it
+       doesn't matter if the user does not
+       actually link against crtbegin.o; the
+       linker won't look for a file to match a
+       wildcard.  The wildcard also means that it
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+       is in.  */
+    KEEP (*crtbegin*.o(.ctors))
+    /* We don't want to include the .ctor section from
+       from the crtend.o file until after the sorted ctors.
+       The .ctor section from the crtend file contains the
+       end of ctors marker and it must be last */
+    KEEP (*(EXCLUDE_FILE (*crtend*.o ) .ctors))
+    KEEP (*(SORT(.ctors.*)))
+    KEEP (*(.ctors))
+  } >CPUSRAM AT>FLASH
+  .dtors          :
+  {
+    KEEP (*crtbegin*.o(.dtors))
+    KEEP (*(EXCLUDE_FILE (*crtend*.o ) .dtors))
+    KEEP (*(SORT(.dtors.*)))
+    KEEP (*(.dtors))
+  } >CPUSRAM AT>FLASH
+  .jcr            : { KEEP (*(.jcr)) } >CPUSRAM AT>FLASH
+  .data.rel.ro : { *(.data.rel.ro.local) *(.data.rel.ro*) } >CPUSRAM AT>FLASH
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+  {
+    *(.data .data.* .gnu.linkonce.d.*)
+    KEEP (*(.gnu.linkonce.d.*personality*))
+    SORT(CONSTRUCTORS)
+  } >CPUSRAM AT>FLASH
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+  .balign	: { . = ALIGN(8); _edata = .; } >CPUSRAM AT>FLASH
+  _edata = .;
+  PROVIDE (edata = .);
+  __bss_start = .;
+  .bss            :
+  {
+   *(.dynbss)
+   *(.bss .bss.* .gnu.linkonce.b.*)
+   *(COMMON)
+   /* Align here to ensure that the .bss section occupies space up to
+      _end.  Align after .bss to ensure correct alignment even if the
+      .bss section disappears because there are no input sections.  */
+   . = ALIGN(8);
+  } >CPUSRAM
+  . = ALIGN(8);
+  _end = .;
+  PROVIDE (end = .);
+  __heap_start__ = ALIGN(8);
+  . = ORIGIN(CPUSRAM) + LENGTH(CPUSRAM) - _stack_size;
+  __heap_end__ = .;
+  /* Stabs debugging sections.  */
+  .stab          0 : { *(.stab) }
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+     Symbols in the DWARF debugging sections are relative to the beginning
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+  .stack         ORIGIN(CPUSRAM) + LENGTH(CPUSRAM) - _stack_size :
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+    . = _stack_size;
+    _estack = .;
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+  /DISCARD/ : { *(.note.GNU-stack) }
+}
diff --git a/bsp/avr32uc3b0/board.c b/bsp/avr32uc3b0/board.c
new file mode 100644
index 000000000..ceb8df815
--- /dev/null
+++ b/bsp/avr32uc3b0/board.c
@@ -0,0 +1,101 @@
+/*
+ * File      : board.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2010-03-30     Kyle         First version
+ */
+
+#include <rtthread.h>
+#include "compiler.h"
+#include "pm.h"
+#include "gpio.h"
+#include "usart.h"
+#include "intc.h"
+#include "serial.h"
+
+#define FOSC0	12000000
+#define FCPU	60000000
+#define FHSB	FCPU
+#define FPBA	FCPU
+#define FPBB	FCPU
+
+extern void rt_hw_serial_isr(void);
+extern void rt_hw_usart_init(void);
+
+/**
+ * System tick interrupt handler.
+ */
+static void rt_hw_timer_handler(void)
+{
+	// Clears the interrupt request.
+	Set_system_register(AVR32_COMPARE, FCPU / RT_TICK_PER_SECOND);
+
+	rt_tick_increase();
+}
+
+/**
+ * Initialize system clock and all peripherals.
+ */
+static void peripherals_init(void)
+{
+	/*
+	 * PM initialization: OSC0 = 12MHz XTAL, PLL0 = 60MHz System Clock
+	 */
+	pm_freq_param_t pm_freq_param =
+	{
+		.cpu_f = FCPU,
+		.pba_f = FPBA,
+		.osc0_f = FOSC0,
+		.osc0_startup = AVR32_PM_OSCCTRL0_STARTUP_2048_RCOSC
+	};
+	pm_configure_clocks(&pm_freq_param);
+
+	/*
+	 * USART1 initialization
+	 */
+	gpio_enable_module_pin(AVR32_USART1_TXD_0_1_PIN, AVR32_USART1_TXD_0_1_FUNCTION);
+	gpio_enable_module_pin(AVR32_USART1_RXD_0_1_PIN, AVR32_USART1_RXD_0_1_FUNCTION);
+	static const usart_options_t usartOptions = {
+		.baudrate = 115200,
+		.charlength = 8,
+		.paritytype = USART_NO_PARITY,
+		.stopbits = USART_1_STOPBIT,
+		.channelmode = USART_NORMAL_CHMODE
+	};
+	usart_init_rs232(&AVR32_USART1, &usartOptions, FCPU);
+
+	INTC_init_interrupts();
+	INTC_register_interrupt(&rt_hw_serial_isr, AVR32_USART1_IRQ, AVR32_INTC_INT0);
+	AVR32_USART1.ier = AVR32_USART_IER_RXRDY_MASK;
+}
+
+/**
+ * Initialize CPU cycle counter for system tick.
+ */
+static void cpu_counter_init(void)
+{
+	INTC_register_interrupt(&rt_hw_timer_handler, AVR32_CORE_COMPARE_IRQ, AVR32_INTC_INT3);
+	Set_system_register(AVR32_COMPARE, FCPU / RT_TICK_PER_SECOND);
+	Set_system_register(AVR32_COUNT, 0);
+}
+
+void rt_hw_board_init(void)
+{
+	extern struct rt_device _rt_usart_device;
+	extern struct avr32_serial_device uart;
+
+	Disable_global_interrupt();
+
+	peripherals_init();
+	cpu_counter_init();
+
+	rt_hw_serial_register(&_rt_usart_device, "uart1", RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX | RT_DEVICE_FLAG_STREAM, &uart);
+	rt_console_set_device("uart1");
+}
diff --git a/bsp/avr32uc3b0/rtconfig.h b/bsp/avr32uc3b0/rtconfig.h
new file mode 100644
index 000000000..2f02170c5
--- /dev/null
+++ b/bsp/avr32uc3b0/rtconfig.h
@@ -0,0 +1,120 @@
+/*
+ * File      : rtconfig.h
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2010-03-30     Kyle         First version
+ */
+
+#ifndef RTCONFIG_H_
+#define RTCONFIG_H_
+
+/* RT_NAME_MAX*/
+#define RT_NAME_MAX	8
+
+/* RT_ALIGN_SIZE*/
+#define RT_ALIGN_SIZE	4
+
+/* PRIORITY_MAX*/
+#define RT_THREAD_PRIORITY_MAX	32
+
+/* Tick per Second*/
+#define RT_TICK_PER_SECOND	100
+
+/* SECTION: RT_DEBUG */
+/* Thread Debug*/
+//#define RT_DEBUG
+/* #define RT_THREAD_DEBUG */
+
+#define RT_USING_OVERFLOW_CHECK
+
+/* Using Hook*/
+//#define RT_USING_HOOK
+
+/* SECTION: IPC */
+/* Using Semaphore*/
+#define RT_USING_SEMAPHORE
+
+/* Using Mutex*/
+//#define RT_USING_MUTEX
+
+/* Using Event*/
+//#define RT_USING_EVENT
+
+/* Using MailBox*/
+//#define RT_USING_MAILBOX
+
+/* Using Message Queue*/
+//#define RT_USING_MESSAGEQUEUE
+
+/* SECTION: Memory Management */
+/* Using Memory Pool Management*/
+#define RT_USING_MEMPOOL
+
+/* Using Dynamic Heap Management*/
+#define RT_USING_HEAP
+
+/* Using Small MM*/
+#define RT_USING_SMALL_MEM
+
+/* Using SLAB Allocator*/
+/* #define RT_USING_SLAB */
+
+/* SECTION: Device System */
+/* Using Device System*/
+#define RT_USING_DEVICE
+
+/* SECTION: Console options */
+/* the buffer size of console*/
+#define RT_CONSOLEBUF_SIZE	128
+
+/* SECTION: FinSH shell options */
+/* Using FinSH as Shell*/
+#define RT_USING_FINSH
+/* Using symbol table */
+#define FINSH_USING_SYMTAB
+#define FINSH_USING_DESCRIPTION
+#define FINSH_DEVICE_NAME   "uart1"
+
+/* SECTION: RT-Thread/GUI */
+//#define RT_USING_DFS
+
+#define RT_USING_DFS_ELMFAT
+#define RT_DFS_ELM_WORD_ACCESS
+#define RT_DFS_ELM_DRIVES			2
+
+/* SECTION: DFS options */
+/* the max number of mounted filesystem */
+#define DFS_FILESYSTEMS_MAX			2
+/* the max number of opened files 		*/
+#define DFS_FD_MAX					8
+/* the max number of cached sector 		*/
+#define DFS_CACHE_MAX_NUM   		4
+
+/* SECTION: RT-Thread/GUI */
+//#define RT_USING_RTGUI
+
+/* name length of RTGUI object */
+#define RTGUI_NAME_MAX		12
+/* support 16 weight font */
+#define RTGUI_USING_FONT16
+/* support Chinese font */
+#define RTGUI_USING_FONTHZ
+/* use DFS as file interface */
+#define RTGUI_USING_DFS_FILERW
+/* use font file as Chinese font */
+#define RTGUI_USING_HZ_FILE
+/* use small size in RTGUI */
+#define RTGUI_USING_SMALL_SIZE
+/* use mouse cursor */
+/* #define RTGUI_USING_MOUSE_CURSOR */
+/* default font size in RTGUI */
+#define RTGUI_DEFAULT_FONT_SIZE	16
+
+#endif /* RTCONFIG_H_ */
diff --git a/bsp/avr32uc3b0/startup.c b/bsp/avr32uc3b0/startup.c
new file mode 100644
index 000000000..7c42c0430
--- /dev/null
+++ b/bsp/avr32uc3b0/startup.c
@@ -0,0 +1,55 @@
+/*
+ * File      : startup.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2010-03-30     Kyle         First version
+ */
+
+#include <rtthread.h>
+
+extern void rt_hw_board_init(void);
+extern void rt_application_init(void);
+
+#ifdef RT_USING_FINSH
+extern void finsh_system_init(void);
+extern void finsh_set_device(const char* device);
+#endif
+
+int main(void)
+{
+#ifdef RT_USING_HEAP
+	extern void __heap_start__;
+	extern void __heap_end__;
+#endif
+
+	rt_hw_board_init();
+	rt_system_tick_init();
+	rt_system_object_init();
+	rt_system_timer_init();
+
+#ifdef RT_USING_HEAP
+	rt_system_heap_init(&__heap_start__, &__heap_end__);
+#endif
+
+	rt_system_scheduler_init();
+	rt_device_init_all();
+	rt_application_init();
+
+#ifdef RT_USING_FINSH
+    /* init finsh */
+    finsh_system_init();
+    finsh_set_device(FINSH_DEVICE_NAME);
+#endif
+
+    rt_thread_idle_init();
+	rt_system_scheduler_start();
+
+	return 0;
+}
diff --git a/libcpu/avr32/uc3/context_gcc.S b/libcpu/avr32/uc3/context_gcc.S
new file mode 100644
index 000000000..1201626ba
--- /dev/null
+++ b/libcpu/avr32/uc3/context_gcc.S
@@ -0,0 +1,97 @@
+/*
+ * File      : context.S
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2010-03-27     Kyle         First version
+ */
+
+#define AVR32_SR			0
+#define AVR32_SR_GM_OFFSET	16
+
+.text
+
+/*
+ * rt_base_t rt_hw_interrupt_disable()
+ */
+.globl rt_hw_interrupt_disable
+.type rt_hw_interrupt_disable, %function
+rt_hw_interrupt_disable:
+	ssrf	AVR32_SR_GM_OFFSET
+	mov		pc, lr
+
+/*
+ * void rt_hw_interrupt_enable(rt_base_t level)
+ */
+.globl rt_hw_interrupt_enable
+.type rt_hw_interrupt_enable, %function
+rt_hw_interrupt_enable:
+	csrf	AVR32_SR_GM_OFFSET
+	mov		pc, lr
+
+/*
+ * void rt_hw_context_switch(rt_uint32 from, rt_uint32 to)/*
+ * r8 --> from
+ * r9 --> to
+ */
+.globl rt_hw_context_switch
+.type rt_hw_context_switch, %function
+rt_hw_context_switch:
+	ssrf	AVR32_SR_GM_OFFSET	/* Disable global interrupt */
+	stm		--sp, r8-r12, lr	/* Push R8-R12, LR */
+	st.w	--sp, lr			/* Push LR (instead of PC) */
+	mfsr	r8, AVR32_SR		/* Read Status Register */
+	cbr		r8, AVR32_SR_GM_OFFSET	/* Clear GM bit */
+	st.w	--sp, r8			/* Push SR */
+	stm		--sp, r0-r7			/* Push R0-R7 */
+								/* Stack layout: R8-R12, LR, PC, SR, R0-R7 */
+
+	st.w	r12[0], sp			/* Store SP in preempted tasks TCB */
+	ld.w	sp, r11[0]			/* Get new task stack pointer */
+
+	ldm		sp++, r0-r7			/* pop R0-R7 */
+	ld.w	r8, sp++			/* pop SR */
+	mtsr	AVR32_SR, r8		/* Restore SR */
+	ldm		sp++, r8-r12, lr, pc/* Pop R8-R12, LR, PC and resume to thread */
+
+/*
+ * void rt_hw_context_switch_to(rt_uint32 to)/*
+ * r0 --> to
+ */
+.globl rt_hw_context_switch_to
+.type rt_hw_context_switch_to, %function
+rt_hw_context_switch_to:
+	ld.w	sp, r12[0]			/* Get new task stack pointer */
+
+	ldm		sp++, r0-r7			/* pop R0-R7 */
+	ld.w	r8, sp++			/* pop SR */
+	mtsr	AVR32_SR, r8		/* Restore SR */
+	ldm		sp++, r8-r12, lr, pc/* Pop R8-R12, LR, PC and resume execution */
+
+/*
+ * void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to)/*
+ */
+.globl rt_thread_switch_interrupt_flag
+.globl rt_interrupt_from_thread
+.globl rt_interrupt_to_thread
+.globl rt_hw_context_switch_interrupt
+.type rt_hw_context_switch_interrupt, %function
+rt_hw_context_switch_interrupt:
+	lda.w	r8, rt_thread_switch_interrupt_flag
+	ld.w	r9, r8[0]
+	cp.w	r9, 1
+	breq	_reswitch
+	mov		r9, 1
+	st.w	r8[0], r9
+	lda.w	r8, rt_interrupt_from_thread
+	st.w	r8[0], r12
+_reswitch:
+	lda.w	r8, rt_interrupt_to_thread
+	st.w	r8[0], r11
+	mov		pc, lr
diff --git a/libcpu/avr32/uc3/cpu.c b/libcpu/avr32/uc3/cpu.c
new file mode 100644
index 000000000..503f2737b
--- /dev/null
+++ b/libcpu/avr32/uc3/cpu.c
@@ -0,0 +1,42 @@
+/*
+ * File      : cpu.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2010-03-30     Kyle         First version
+ */
+
+#include <rtthread.h>
+
+/**
+ * @addtogroup AVR32UC3
+ */
+/*@{*/
+
+/**
+ * reset cpu by dog's time-out
+ *
+ */
+void rt_hw_cpu_reset()
+{
+	/*NOTREACHED*/
+}
+
+/**
+ *  shutdown CPU
+ *
+ */
+void rt_hw_cpu_shutdown()
+{
+	rt_kprintf("shutdown...\n");
+
+	RT_ASSERT(0);
+}
+
+/*@}*/
diff --git a/libcpu/avr32/uc3/exception.S b/libcpu/avr32/uc3/exception.S
new file mode 100644
index 000000000..dabd93d88
--- /dev/null
+++ b/libcpu/avr32/uc3/exception.S
@@ -0,0 +1,245 @@
+/* This file is part of the ATMEL AVR32-UC3-SoftwareFramework-1.6.0 Release */
+
+/*This file is prepared for Doxygen automatic documentation generation.*/
+/*! \file *********************************************************************
+ *
+ * \brief Exception and interrupt vectors.
+ *
+ * This file maps all events supported by an AVR32.
+ *
+ * - Compiler:           GNU GCC for AVR32
+ * - Supported devices:  All AVR32 devices with an INTC module can be used.
+ * - AppNote:
+ *
+ * \author               Atmel Corporation: http://www.atmel.com \n
+ *                       Support and FAQ: http://support.atmel.no/
+ *
+ ******************************************************************************/
+
+/* Copyright (c) 2009 Atmel Corporation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * 3. The name of Atmel may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * 4. This software may only be redistributed and used in connection with an Atmel
+ * AVR product.
+ *
+ * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE
+ *
+ */
+
+#if !__AVR32_UC__ && !__AVR32_AP__
+  #error Implementation of the AVR32 architecture not supported by the INTC driver.
+#endif
+
+
+#include <avr32/io.h>
+
+
+//! @{
+//! \verbatim
+
+
+  .section  .exception, "ax", @progbits
+
+
+// Start of Exception Vector Table.
+
+  // EVBA must be aligned with a power of two strictly greater than the EVBA-
+  // relative offset of the last vector.
+  .balign 0x200
+
+  // Export symbol.
+  .global _evba
+  .type _evba, @function
+_evba:
+
+        .org  0x000
+        // Unrecoverable Exception.
+_handle_Unrecoverable_Exception:
+        rjmp $
+
+        .org  0x004
+        // TLB Multiple Hit.
+_handle_TLB_Multiple_Hit:
+        rjmp $
+
+        .org  0x008
+        // Bus Error Data Fetch.
+_handle_Bus_Error_Data_Fetch:
+        rjmp $
+
+        .org  0x00C
+         // Bus Error Instruction Fetch.
+_handle_Bus_Error_Instruction_Fetch:
+        rjmp $
+
+        .org  0x010
+        // NMI.
+_handle_NMI:
+        rjmp $
+
+        .org  0x014
+        // Instruction Address.
+_handle_Instruction_Address:
+        rjmp $
+
+        .org  0x018
+        // ITLB Protection.
+_handle_ITLB_Protection:
+        rjmp $
+
+        .org  0x01C
+        // Breakpoint.
+_handle_Breakpoint:
+        rjmp $
+
+        .org  0x020
+        // Illegal Opcode.
+_handle_Illegal_Opcode:
+        rjmp $
+
+        .org  0x024
+        // Unimplemented Instruction.
+_handle_Unimplemented_Instruction:
+        rjmp $
+
+        .org  0x028
+        // Privilege Violation.
+_handle_Privilege_Violation:
+        rjmp $
+
+        .org  0x02C
+        // Floating-Point: UNUSED IN AVR32UC and AVR32AP.
+_handle_Floating_Point:
+        rjmp $
+
+        .org  0x030
+        // Coprocessor Absent: UNUSED IN AVR32UC.
+_handle_Coprocessor_Absent:
+        rjmp $
+
+        .org  0x034
+        // Data Address (Read).
+_handle_Data_Address_Read:
+        rjmp $
+
+        .org  0x038
+        // Data Address (Write).
+_handle_Data_Address_Write:
+        rjmp $
+
+        .org  0x03C
+        // DTLB Protection (Read).
+_handle_DTLB_Protection_Read:
+        rjmp $
+
+        .org  0x040
+        // DTLB Protection (Write).
+_handle_DTLB_Protection_Write:
+        rjmp $
+
+        .org  0x044
+        // DTLB Modified: UNUSED IN AVR32UC.
+_handle_DTLB_Modified:
+        rjmp $
+
+        .org  0x050
+        // ITLB Miss.
+_handle_ITLB_Miss:
+        rjmp $
+
+        .org  0x060
+        // DTLB Miss (Read).
+_handle_DTLB_Miss_Read:
+        rjmp $
+
+        .org  0x070
+        // DTLB Miss (Write).
+_handle_DTLB_Miss_Write:
+        rjmp $
+
+        .org  0x100
+        // Supervisor Call.
+_handle_Supervisor_Call:
+        rjmp $
+
+
+// Interrupt support.
+// The interrupt controller must provide the offset address relative to EVBA.
+// Important note:
+//   All interrupts call a C function named _get_interrupt_handler.
+//   This function will read group and interrupt line number to then return in
+//   R12 a pointer to a user-provided interrupt handler.
+
+  .balign 4
+
+  .irp    priority, 0, 1, 2, 3
+_int\priority:
+  mov     r12, \priority  // Pass the int_level parameter to the _get_interrupt_handler function.
+  call    _get_interrupt_handler
+  cp.w    r12, 0          // Get the pointer to the interrupt handler returned by the function.
+  breq    _spint\priority // If this was not a spurious interrupt (R12 != NULL), jump to the handler.
+  call    rt_interrupt_enter
+  icall   r12
+  call    rt_interrupt_leave
+_spint\priority:
+  lda.w   r12, rt_thread_switch_interrupt_flag
+  ld.w    r11, r12[0]
+  cp.w    r11, 1
+  breq    rt_hw_context_switch_interrupt_do
+  rete                    // If this was a spurious interrupt (R12 == NULL), return from event handler.
+  .endr
+
+rt_hw_context_switch_interrupt_do:
+  ssrf    AVR32_SR_GM_OFFSET			/* Disable global interrupt */
+  mov     r11, 0
+  st.w    r12[0], r11					/* Clear rt_thread_switch_interrupt_flag */
+  stm     --sp, r0-r7					/* Push R0-R7 */
+  lda.w   r12, rt_interrupt_from_thread	/* Get old thread SP */
+  ld.w    r12, r12[0]
+  lda.w   r11, rt_interrupt_to_thread	/* Get new thread SP */
+  ld.w    r11, r11[0]
+  st.w    r12[0], sp					/* Store old thead SP */
+  ld.w    sp, r11[0]					/* Load new thread SP */
+  ldm     sp++, r0-r7					/* Pop R0-R7 (new thread) */
+  rete									/* RETE pops R8-R12, LR, PC, SR automatically */
+
+
+// Constant data area.
+
+  .balign 4
+
+  // Values to store in the interrupt priority registers for the various interrupt priority levels.
+  // The interrupt priority registers contain the interrupt priority level and
+  // the EVBA-relative interrupt vector offset.
+  .global ipr_val
+  .type ipr_val, @object
+ipr_val:
+  .word (AVR32_INTC_INT0 << AVR32_INTC_IPR_INTLEVEL_OFFSET) | (_int0 - _evba),\
+        (AVR32_INTC_INT1 << AVR32_INTC_IPR_INTLEVEL_OFFSET) | (_int1 - _evba),\
+        (AVR32_INTC_INT2 << AVR32_INTC_IPR_INTLEVEL_OFFSET) | (_int2 - _evba),\
+        (AVR32_INTC_INT3 << AVR32_INTC_IPR_INTLEVEL_OFFSET) | (_int3 - _evba)
+
+
+//! \endverbatim
+//! @}
diff --git a/libcpu/avr32/uc3/interrupt.c b/libcpu/avr32/uc3/interrupt.c
new file mode 100644
index 000000000..7cfa71d50
--- /dev/null
+++ b/libcpu/avr32/uc3/interrupt.c
@@ -0,0 +1,19 @@
+/*
+ * File      : interrupt.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2010-03-30     Kyle         Ported from STM32 to AVR32.
+ */
+
+#include <rtthread.h>
+#include "compiler.h"
+
+rt_uint32_t rt_interrupt_from_thread, rt_interrupt_to_thread;
+rt_uint32_t rt_thread_switch_interrupt_flag;
diff --git a/libcpu/avr32/uc3/serial.c b/libcpu/avr32/uc3/serial.c
new file mode 100644
index 000000000..e68423353
--- /dev/null
+++ b/libcpu/avr32/uc3/serial.c
@@ -0,0 +1,278 @@
+/*
+ * File      : serial.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2009-02-05     Bernard      first version
+ * 2009-10-25     Bernard      fix rt_serial_read bug when there is no data
+ *                             in the buffer.
+ * 2010-03-29     Bernard      cleanup code.
+ * 2010-03-30     Kyle         Ported from STM32 to AVR32.
+ */
+
+#include "serial.h"
+#include "compiler.h"
+#include "usart.h"
+#include "pdca.h"
+
+struct rt_device _rt_usart_device;
+struct avr32_serial_int_rx _rt_usart_rx;
+struct avr32_serial_device uart =
+{
+	.uart_device = (avr32_usart_t *) &AVR32_USART1,
+	.int_rx = &_rt_usart_rx
+};
+
+/**
+ * @addtogroup AVR32UC3
+ */
+/*@{*/
+
+/* RT-Thread Device Interface */
+static rt_err_t rt_serial_init (rt_device_t dev)
+{
+	struct avr32_serial_device* uart = (struct avr32_serial_device*) dev->private;
+
+	if (!(dev->flag & RT_DEVICE_FLAG_ACTIVATED))
+	{
+		if (dev->flag & RT_DEVICE_FLAG_INT_RX)
+		{
+			rt_memset(uart->int_rx->rx_buffer, 0, sizeof(uart->int_rx->rx_buffer));
+			uart->int_rx->read_index = 0;
+			uart->int_rx->save_index = 0;
+		}
+
+		dev->flag |= RT_DEVICE_FLAG_ACTIVATED;
+	}
+
+	return RT_EOK;
+}
+
+static rt_err_t rt_serial_open(rt_device_t dev, rt_uint16_t oflag)
+{
+	return RT_EOK;
+}
+
+static rt_err_t rt_serial_close(rt_device_t dev)
+{
+	return RT_EOK;
+}
+
+static rt_size_t rt_serial_read (rt_device_t dev, rt_off_t pos, void* buffer, rt_size_t size)
+{
+	rt_uint8_t* ptr;
+	rt_err_t err_code;
+	struct avr32_serial_device* uart;
+
+	ptr = buffer;
+	err_code = RT_EOK;
+	uart = (struct avr32_serial_device*)dev->private;
+
+	if (dev->flag & RT_DEVICE_FLAG_INT_RX)
+	{
+		/* interrupt mode Rx */
+		while (size)
+		{
+			rt_base_t level;
+
+			/* disable interrupt */
+			level = rt_hw_interrupt_disable();
+
+			if (uart->int_rx->read_index != uart->int_rx->save_index)
+			{
+				/* read a character */
+				*ptr++ = uart->int_rx->rx_buffer[uart->int_rx->read_index];
+				size--;
+
+				/* move to next position */
+				uart->int_rx->read_index ++;
+				if (uart->int_rx->read_index >= UART_RX_BUFFER_SIZE)
+					uart->int_rx->read_index = 0;
+			}
+			else
+			{
+				/* set error code */
+				err_code = -RT_EEMPTY;
+
+				/* enable interrupt */
+				rt_hw_interrupt_enable(level);
+				break;
+			}
+
+			/* enable interrupt */
+			rt_hw_interrupt_enable(level);
+		}
+	}
+	else
+	{
+		/* polling mode */
+		while ((rt_uint32_t)ptr - (rt_uint32_t)buffer < size)
+		{
+			while (usart_test_hit(uart->uart_device))
+			{
+				*ptr = uart->uart_device->rhr & 0xff;
+				ptr ++;
+			}
+		}
+	}
+
+	/* set error code */
+	rt_set_errno(err_code);
+	return (rt_uint32_t)ptr - (rt_uint32_t)buffer;
+}
+
+static rt_size_t rt_serial_write (rt_device_t dev, rt_off_t pos, const void* buffer, rt_size_t size)
+{
+	rt_uint8_t* ptr;
+	rt_err_t err_code;
+	struct avr32_serial_device* uart;
+
+	err_code = RT_EOK;
+	ptr = (rt_uint8_t*)buffer;
+	uart = (struct avr32_serial_device*)dev->private;
+
+	if (dev->flag & RT_DEVICE_FLAG_INT_TX)
+	{
+		/* interrupt mode Tx, does not support */
+		RT_ASSERT(0);
+	}
+	else
+	{
+		/* polling mode */
+		if (dev->flag & RT_DEVICE_FLAG_STREAM)
+		{
+			/* stream mode */
+			while (size)
+			{
+				usart_putchar(uart->uart_device, (int) *ptr);
+
+				++ptr; --size;
+			}
+		}
+		else
+		{
+			/* write data directly */
+			while (size)
+			{
+				while (usart_write_char(uart->uart_device, (int) *ptr) != USART_SUCCESS);
+
+				++ptr; --size;
+			}
+		}
+	}
+
+	/* set error code */
+	rt_set_errno(err_code);
+
+	return (rt_uint32_t)ptr - (rt_uint32_t)buffer;
+}
+
+static rt_err_t rt_serial_control (rt_device_t dev, rt_uint8_t cmd, void *args)
+{
+	struct avr32_serial_device* uart;
+
+	RT_ASSERT(dev != RT_NULL);
+
+	uart = (struct avr32_serial_device*)dev->private;
+	switch (cmd)
+	{
+	case RT_DEVICE_CTRL_SUSPEND:
+		/* suspend device */
+		dev->flag |= RT_DEVICE_FLAG_SUSPENDED;
+		break;
+
+	case RT_DEVICE_CTRL_RESUME:
+		/* resume device */
+		dev->flag &= ~RT_DEVICE_FLAG_SUSPENDED;
+		break;
+	}
+
+	return RT_EOK;
+}
+
+/*
+ * serial register for STM32
+ * support STM32F103VB and STM32F103ZE
+ */
+rt_err_t rt_hw_serial_register(rt_device_t device, const char* name, rt_uint32_t flag, struct avr32_serial_device *serial)
+{
+	RT_ASSERT(device != RT_NULL);
+
+	if ((flag & RT_DEVICE_FLAG_DMA_RX) ||
+		(flag & RT_DEVICE_FLAG_INT_TX))
+	{
+		RT_ASSERT(0);
+	}
+
+	device->type 		= RT_Device_Class_Char;
+	device->rx_indicate = RT_NULL;
+	device->tx_complete = RT_NULL;
+	device->init 		= rt_serial_init;
+	device->open		= rt_serial_open;
+	device->close		= rt_serial_close;
+	device->read 		= rt_serial_read;
+	device->write 		= rt_serial_write;
+	device->control 	= rt_serial_control;
+	device->private		= serial;
+
+	/* register a character device */
+	return rt_device_register(device, name, RT_DEVICE_FLAG_RDWR | flag);
+}
+
+/* ISR for serial interrupt */
+void rt_hw_serial_isr(void)
+{
+	struct avr32_serial_device* uart = (struct avr32_serial_device*) _rt_usart_device.private;
+	rt_base_t level;
+
+	if (usart_test_hit(uart->uart_device))
+	{
+		/* interrupt mode receive */
+		RT_ASSERT(device->flag & RT_DEVICE_FLAG_INT_RX);
+
+		/* disable interrupt */
+		level = rt_hw_interrupt_disable();
+
+		/* save character */
+		uart->int_rx->rx_buffer[uart->int_rx->save_index] = uart->uart_device->rhr & 0xff;
+		uart->int_rx->save_index ++;
+		if (uart->int_rx->save_index >= UART_RX_BUFFER_SIZE)
+			uart->int_rx->save_index = 0;
+
+		/* if the next position is read index, discard this 'read char' */
+		if (uart->int_rx->save_index == uart->int_rx->read_index)
+		{
+			uart->int_rx->read_index ++;
+			if (uart->int_rx->read_index >= UART_RX_BUFFER_SIZE)
+				uart->int_rx->read_index = 0;
+		}
+
+		/* enable interrupt */
+		rt_hw_interrupt_enable(level);
+
+		/* invoke callback */
+		if (_rt_usart_device.rx_indicate != RT_NULL)
+		{
+			rt_size_t rx_length;
+
+			/* get rx length */
+			rx_length = uart->int_rx->read_index > uart->int_rx->save_index ?
+				UART_RX_BUFFER_SIZE - uart->int_rx->read_index + uart->int_rx->save_index :
+				uart->int_rx->save_index - uart->int_rx->read_index;
+
+			_rt_usart_device.rx_indicate(&_rt_usart_device, rx_length);
+		}
+	}
+	else
+	{
+		usart_reset_status(uart->uart_device);
+	}
+}
+
+/*@}*/
diff --git a/libcpu/avr32/uc3/serial.h b/libcpu/avr32/uc3/serial.h
new file mode 100644
index 000000000..cadbfd185
--- /dev/null
+++ b/libcpu/avr32/uc3/serial.h
@@ -0,0 +1,53 @@
+/*
+ * File      : serial.h
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2009 - 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2009-01-05     Bernard      first version
+ * 2010-03-29     Bernard      remove interrupt tx and DMA rx mode.
+ * 2010-03-30     Kyle         Ported from STM32 to AVR32.
+ */
+#ifndef __RT_HW_SERIAL_H__
+#define __RT_HW_SERIAL_H__
+
+#include <rthw.h>
+#include <rtthread.h>
+#include "compiler.h"
+#include "usart.h"
+
+#define UART_RX_BUFFER_SIZE		64
+#define UART_TX_DMA_NODE_SIZE	4
+
+/* data node for Tx Mode */
+struct avr32_serial_data_node
+{
+	rt_uint8_t *data_ptr;
+	rt_size_t  data_size;
+	struct avr32_serial_data_node *next, *prev;
+};
+
+struct avr32_serial_int_rx
+{
+	rt_uint8_t  rx_buffer[UART_RX_BUFFER_SIZE];
+	rt_uint32_t read_index, save_index;
+};
+
+struct avr32_serial_device
+{
+	avr32_usart_t *uart_device;
+
+	/* rx structure */
+	struct avr32_serial_int_rx* int_rx;
+};
+
+rt_err_t rt_hw_serial_register(rt_device_t device, const char* name, rt_uint32_t flag, struct avr32_serial_device *serial);
+
+void rt_hw_serial_isr();
+
+#endif
diff --git a/libcpu/avr32/uc3/stack.c b/libcpu/avr32/uc3/stack.c
new file mode 100644
index 000000000..e187f84ce
--- /dev/null
+++ b/libcpu/avr32/uc3/stack.c
@@ -0,0 +1,57 @@
+/*
+ * File      : stack.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2010, RT-Thread Development Team
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rt-thread.org/license/LICENSE
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2010-03-30     Kyle         First version
+ */
+#include <rtthread.h>
+
+/**
+ * @addtogroup AVR32UC3
+ */
+/*@{*/
+
+/**
+ * This function will initialize thread stack
+ *
+ * @param tentry the entry of thread
+ * @param parameter the parameter of entry
+ * @param stack_addr the beginning stack address
+ * @param texit the function will be called when thread exit
+ *
+ * @return stack address
+ */
+rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter, rt_uint8_t *stack_addr, void *texit)
+{
+	unsigned long *stk;
+
+	stk 	 = (unsigned long *)stack_addr;
+	*(stk)   = 0;							/* r8 */
+	*(--stk) = 0;							/* r9 */
+	*(--stk) = 0;							/* r10 */
+	*(--stk) = 0;							/* r11 */
+	*(--stk) = 0;							/* r12 */
+	*(--stk) = (unsigned long)texit;		/* lr */
+	*(--stk) = (unsigned long)tentry;		/* entry point, pc */
+	*(--stk) = 0x00600000;					/* sr */
+	*(--stk) = 0;							/* r0 */
+	*(--stk) = 0;							/* r1 */
+	*(--stk) = 0;							/* r2 */
+	*(--stk) = 0;							/* r3 */
+	*(--stk) = 0;							/* r4 */
+	*(--stk) = 0;							/* r5 */
+	*(--stk) = 0;							/* r6 */
+	*(--stk) = 0;							/* r7 */
+
+	/* return task's current stack address */
+	return (rt_uint8_t *)stk;
+}
+
+/*@}*/