diff --git a/examples/device/msc_dual_lun/skip.txt b/examples/device/msc_dual_lun/skip.txt
index 4d607dc05..a9e3a99b1 100644
--- a/examples/device/msc_dual_lun/skip.txt
+++ b/examples/device/msc_dual_lun/skip.txt
@@ -1,4 +1,3 @@
-mcu:CH32V20X
 mcu:SAMD11
 mcu:MKL25ZXX
 family:espressif
diff --git a/examples/device/msc_dual_lun/src/msc_disk_dual.c b/examples/device/msc_dual_lun/src/msc_disk_dual.c
index 4f0f6410f..81f1d3346 100644
--- a/examples/device/msc_dual_lun/src/msc_disk_dual.c
+++ b/examples/device/msc_dual_lun/src/msc_disk_dual.c
@@ -34,9 +34,13 @@
 // Some MCU doesn't have enough 8KB SRAM to store the whole disk
 // We will use Flash as read-only disk with board that has
 // CFG_EXAMPLE_MSC_READONLY defined
+#if defined(CFG_EXAMPLE_MSC_READONLY) || defined(CFG_EXAMPLE_MSC_DUAL_READONLY)
+  #define MSC_CONST const
+#else
+  #define MSC_CONST
+#endif
 
-enum
-{
+enum {
   DISK_BLOCK_NUM  = 16, // 8KB is the smallest size that windows allow to mount
   DISK_BLOCK_SIZE = 512
 };
@@ -51,10 +55,7 @@ If you find any bugs or get any questions, feel free to file an\r\n\
 issue at github.com/hathach/tinyusb"
 
 
-#ifdef CFG_EXAMPLE_MSC_READONLY
-const
-#endif
-uint8_t msc_disk0[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
+MSC_CONST uint8_t msc_disk0[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
 {
   //------------- Block0: Boot Sector -------------//
   // byte_per_sector    = DISK_BLOCK_SIZE; fat12_sector_num_16  = DISK_BLOCK_NUM;
@@ -132,10 +133,7 @@ uint8_t msc_disk0[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
 If you find any bugs or get any questions, feel free to file an\r\n\
 issue at github.com/hathach/tinyusb"
 
-#ifdef CFG_EXAMPLE_MSC_READONLY
-const
-#endif
-uint8_t msc_disk1[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
+MSC_CONST uint8_t msc_disk1[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
 {
   //------------- Block0: Boot Sector -------------//
   // byte_per_sector    = DISK_BLOCK_SIZE; fat12_sector_num_16  = DISK_BLOCK_NUM;
@@ -206,15 +204,13 @@ uint8_t msc_disk1[DISK_BLOCK_NUM][DISK_BLOCK_SIZE] =
 };
 
 // Invoked to determine max LUN
-uint8_t tud_msc_get_maxlun_cb(void)
-{
+uint8_t tud_msc_get_maxlun_cb(void) {
   return 2; // dual LUN
 }
 
 // Invoked when received SCSI_CMD_INQUIRY
 // Application fill vendor id, product id and revision with string up to 8, 16, 4 characters respectively
-void tud_msc_inquiry_cb(uint8_t lun, uint8_t vendor_id[8], uint8_t product_id[16], uint8_t product_rev[4])
-{
+void tud_msc_inquiry_cb(uint8_t lun, uint8_t vendor_id[8], uint8_t product_id[16], uint8_t product_rev[4]) {
   (void) lun; // use same ID for both LUNs
 
   const char vid[] = "TinyUSB";
@@ -228,8 +224,7 @@ void tud_msc_inquiry_cb(uint8_t lun, uint8_t vendor_id[8], uint8_t product_id[16
 
 // Invoked when received Test Unit Ready command.
 // return true allowing host to read/write this LUN e.g SD card inserted
-bool tud_msc_test_unit_ready_cb(uint8_t lun)
-{
+bool tud_msc_test_unit_ready_cb(uint8_t lun) {
   if ( lun == 1 && board_button_read() ) return false;
 
   return true; // RAM disk is always ready
@@ -237,8 +232,7 @@ bool tud_msc_test_unit_ready_cb(uint8_t lun)
 
 // Invoked when received SCSI_CMD_READ_CAPACITY_10 and SCSI_CMD_READ_FORMAT_CAPACITY to determine the disk size
 // Application update block count and block size
-void tud_msc_capacity_cb(uint8_t lun, uint32_t* block_count, uint16_t* block_size)
-{
+void tud_msc_capacity_cb(uint8_t lun, uint32_t* block_count, uint16_t* block_size) {
   (void) lun;
 
   *block_count = DISK_BLOCK_NUM;
@@ -248,18 +242,14 @@ void tud_msc_capacity_cb(uint8_t lun, uint32_t* block_count, uint16_t* block_siz
 // Invoked when received Start Stop Unit command
 // - Start = 0 : stopped power mode, if load_eject = 1 : unload disk storage
 // - Start = 1 : active mode, if load_eject = 1 : load disk storage
-bool tud_msc_start_stop_cb(uint8_t lun, uint8_t power_condition, bool start, bool load_eject)
-{
+bool tud_msc_start_stop_cb(uint8_t lun, uint8_t power_condition, bool start, bool load_eject) {
   (void) lun;
   (void) power_condition;
 
-  if ( load_eject )
-  {
-    if (start)
-    {
+  if (load_eject) {
+    if (start) {
       // load disk storage
-    }else
-    {
+    } else {
       // unload disk storage
     }
   }
@@ -269,10 +259,9 @@ bool tud_msc_start_stop_cb(uint8_t lun, uint8_t power_condition, bool start, boo
 
 // Callback invoked when received READ10 command.
 // Copy disk's data to buffer (up to bufsize) and return number of copied bytes.
-int32_t tud_msc_read10_cb(uint8_t lun, uint32_t lba, uint32_t offset, void* buffer, uint32_t bufsize)
-{
+int32_t tud_msc_read10_cb(uint8_t lun, uint32_t lba, uint32_t offset, void* buffer, uint32_t bufsize) {
   // out of ramdisk
-  if ( lba >= DISK_BLOCK_NUM ) return -1;
+  if (lba >= DISK_BLOCK_NUM) return -1;
 
   uint8_t const* addr = (lun ? msc_disk1[lba] : msc_disk0[lba]) + offset;
   memcpy(buffer, addr, bufsize);
@@ -280,11 +269,10 @@ int32_t tud_msc_read10_cb(uint8_t lun, uint32_t lba, uint32_t offset, void* buff
   return (int32_t) bufsize;
 }
 
-bool tud_msc_is_writable_cb (uint8_t lun)
-{
+bool tud_msc_is_writable_cb(uint8_t lun) {
   (void) lun;
 
-#ifdef CFG_EXAMPLE_MSC_READONLY
+#if defined(CFG_EXAMPLE_MSC_READONLY) || defined(CFG_EXAMPLE_MSC_DUAL_READONLY)
   return false;
 #else
   return true;
@@ -293,16 +281,18 @@ bool tud_msc_is_writable_cb (uint8_t lun)
 
 // Callback invoked when received WRITE10 command.
 // Process data in buffer to disk's storage and return number of written bytes
-int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t* buffer, uint32_t bufsize)
-{
+int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t* buffer, uint32_t bufsize) {
   // out of ramdisk
-  if ( lba >= DISK_BLOCK_NUM ) return -1;
+  if (lba >= DISK_BLOCK_NUM) return -1;
 
-#ifndef CFG_EXAMPLE_MSC_READONLY
+#if defined(CFG_EXAMPLE_MSC_READONLY) || defined(CFG_EXAMPLE_MSC_DUAL_READONLY)
+  (void) lun;
+  (void) lba;
+  (void) offset;
+  (void) buffer;
+#else
   uint8_t* addr = (lun ? msc_disk1[lba] : msc_disk0[lba])  + offset;
   memcpy(addr, buffer, bufsize);
-#else
-  (void) lun; (void) lba; (void) offset; (void) buffer;
 #endif
 
   return (int32_t) bufsize;
@@ -311,8 +301,7 @@ int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t*
 // Callback invoked when received an SCSI command not in built-in list below
 // - READ_CAPACITY10, READ_FORMAT_CAPACITY, INQUIRY, MODE_SENSE6, REQUEST_SENSE
 // - READ10 and WRITE10 has their own callbacks
-int32_t tud_msc_scsi_cb (uint8_t lun, uint8_t const scsi_cmd[16], void* buffer, uint16_t bufsize)
-{
+int32_t tud_msc_scsi_cb(uint8_t lun, uint8_t const scsi_cmd[16], void* buffer, uint16_t bufsize) {
   // read10 & write10 has their own callback and MUST not be handled here
 
   void const* response = NULL;
@@ -321,27 +310,23 @@ int32_t tud_msc_scsi_cb (uint8_t lun, uint8_t const scsi_cmd[16], void* buffer,
   // most scsi handled is input
   bool in_xfer = true;
 
-  switch (scsi_cmd[0])
-  {
+  switch (scsi_cmd[0]) {
     default:
       // Set Sense = Invalid Command Operation
       tud_msc_set_sense(lun, SCSI_SENSE_ILLEGAL_REQUEST, 0x20, 0x00);
 
       // negative means error -> tinyusb could stall and/or response with failed status
       resplen = -1;
-    break;
+      break;
   }
 
   // return resplen must not larger than bufsize
-  if ( resplen > bufsize ) resplen = bufsize;
+  if (resplen > bufsize) resplen = bufsize;
 
-  if ( response && (resplen > 0) )
-  {
-    if(in_xfer)
-    {
+  if (response && (resplen > 0)) {
+    if (in_xfer) {
       memcpy(buffer, response, (size_t) resplen);
-    }else
-    {
+    } else {
       // SCSI output
     }
   }
diff --git a/hw/bsp/ch32v20x/boards/ch32v203_r0_1v0/board.cmake b/hw/bsp/ch32v20x/boards/ch32v203_r0_1v0/board.cmake
new file mode 100644
index 000000000..8d3e0326e
--- /dev/null
+++ b/hw/bsp/ch32v20x/boards/ch32v203_r0_1v0/board.cmake
@@ -0,0 +1,10 @@
+set(MCU_VARIANT D6)
+
+set(LD_FLASH_SIZE 64K)
+set(LD_RAM_SIZE 20K)
+
+function(update_board TARGET)
+  target_compile_definitions(${TARGET} PUBLIC
+    CFG_EXAMPLE_MSC_DUAL_READONLY
+    )
+endfunction()
diff --git a/hw/bsp/ch32v20x/boards/ch32v203_r0_1v0/board.h b/hw/bsp/ch32v20x/boards/ch32v203_r0_1v0/board.h
new file mode 100644
index 000000000..c8d28d90f
--- /dev/null
+++ b/hw/bsp/ch32v20x/boards/ch32v203_r0_1v0/board.h
@@ -0,0 +1,17 @@
+#ifndef BOARD_H_
+#define BOARD_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define LED_PORT       GPIOA
+#define LED_PIN        GPIO_Pin_15
+#define LED_STATE_ON   0
+#define LED_CLOCK_EN() RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/hw/bsp/ch32v20x/boards/ch32v203_r0_1v0/board.mk b/hw/bsp/ch32v20x/boards/ch32v203_r0_1v0/board.mk
new file mode 100644
index 000000000..7d7462312
--- /dev/null
+++ b/hw/bsp/ch32v20x/boards/ch32v203_r0_1v0/board.mk
@@ -0,0 +1,7 @@
+MCU_VARIANT = D6
+
+CFLAGS += -DCFG_EXAMPLE_MSC_DUAL_READONLY
+
+LDFLAGS += \
+  -Wl,--defsym=__flash_size=64K \
+  -Wl,--defsym=__ram_size=20K \
diff --git a/hw/bsp/ch32v20x/boards/nanoch32v203/board.cmake b/hw/bsp/ch32v20x/boards/nanoch32v203/board.cmake
index 2699f3e15..8d3e0326e 100644
--- a/hw/bsp/ch32v20x/boards/nanoch32v203/board.cmake
+++ b/hw/bsp/ch32v20x/boards/nanoch32v203/board.cmake
@@ -1,7 +1,10 @@
 set(MCU_VARIANT D6)
 
+set(LD_FLASH_SIZE 64K)
+set(LD_RAM_SIZE 20K)
+
 function(update_board TARGET)
   target_compile_definitions(${TARGET} PUBLIC
-    CH32V20x_D6
+    CFG_EXAMPLE_MSC_DUAL_READONLY
     )
 endfunction()
diff --git a/hw/bsp/ch32v20x/boards/nanoch32v203/board.mk b/hw/bsp/ch32v20x/boards/nanoch32v203/board.mk
index 75dc05457..7d7462312 100644
--- a/hw/bsp/ch32v20x/boards/nanoch32v203/board.mk
+++ b/hw/bsp/ch32v20x/boards/nanoch32v203/board.mk
@@ -1,5 +1,7 @@
-CFLAGS += \
-	-DCH32V20x_D6
+MCU_VARIANT = D6
 
-SRC_S += \
-	$(CH32V20X_SDK_SRC)/Startup/startup_ch32v20x_D6.S
+CFLAGS += -DCFG_EXAMPLE_MSC_DUAL_READONLY
+
+LDFLAGS += \
+  -Wl,--defsym=__flash_size=64K \
+  -Wl,--defsym=__ram_size=20K \
diff --git a/hw/bsp/ch32v20x/family.cmake b/hw/bsp/ch32v20x/family.cmake
index fb39e3630..80b035fc0 100644
--- a/hw/bsp/ch32v20x/family.cmake
+++ b/hw/bsp/ch32v20x/family.cmake
@@ -1,7 +1,8 @@
 include_guard()
 
 set(CH32_FAMILY ch32v20x)
-set(SDK_DIR ${TOP}/hw/mcu/wch/${CH32_FAMILY}/EVT/EXAM/SRC)
+set(SDK_DIR ${TOP}/hw/mcu/wch/${CH32_FAMILY})
+set(SDK_SRC_DIR ${SDK_DIR}/EVT/EXAM/SRC)
 
 # include board specific
 include(${CMAKE_CURRENT_LIST_DIR}/boards/${BOARD}/board.cmake)
@@ -23,29 +24,30 @@ function(add_board_target BOARD_TARGET)
   endif()
 
   if (NOT DEFINED LD_FILE_GNU)
-    set(LD_FILE_GNU ${SDK_DIR}/Ld/Link.ld)
+    set(LD_FILE_GNU ${CMAKE_CURRENT_FUNCTION_LIST_DIR}/linker/${CH32_FAMILY}.ld)
   endif ()
   set(LD_FILE_Clang ${LD_FILE_GNU})
 
   if (NOT DEFINED STARTUP_FILE_GNU)
-    set(STARTUP_FILE_GNU ${SDK_DIR}/Startup/startup_${CH32_FAMILY}_${MCU_VARIANT}.S)
+    set(STARTUP_FILE_GNU ${SDK_SRC_DIR}/Startup/startup_${CH32_FAMILY}_${MCU_VARIANT}.S)
   endif ()
   set(STARTUP_FILE_Clang ${STARTUP_FILE_GNU})
 
   add_library(${BOARD_TARGET} STATIC
-    ${SDK_DIR}/Core/core_riscv.c
-    ${SDK_DIR}/Peripheral/src/${CH32_FAMILY}_gpio.c
-    ${SDK_DIR}/Peripheral/src/${CH32_FAMILY}_misc.c
-    ${SDK_DIR}/Peripheral/src/${CH32_FAMILY}_rcc.c
-    ${SDK_DIR}/Peripheral/src/${CH32_FAMILY}_usart.c
+    ${SDK_SRC_DIR}/Core/core_riscv.c
+    ${SDK_SRC_DIR}/Peripheral/src/${CH32_FAMILY}_gpio.c
+    ${SDK_SRC_DIR}/Peripheral/src/${CH32_FAMILY}_misc.c
+    ${SDK_SRC_DIR}/Peripheral/src/${CH32_FAMILY}_rcc.c
+    ${SDK_SRC_DIR}/Peripheral/src/${CH32_FAMILY}_usart.c
     ${CMAKE_CURRENT_FUNCTION_LIST_DIR}/system_${CH32_FAMILY}.c
     ${STARTUP_FILE_${CMAKE_C_COMPILER_ID}}
     )
   target_include_directories(${BOARD_TARGET} PUBLIC
-    ${SDK_DIR}/Peripheral/inc
+    ${SDK_SRC_DIR}/Peripheral/inc
     ${CMAKE_CURRENT_FUNCTION_LIST_DIR}
     )
   target_compile_definitions(${BOARD_TARGET} PUBLIC
+    CH32V20x_${MCU_VARIANT}
     BOARD_TUD_MAX_SPEED=OPT_MODE_FULL_SPEED
     )
 
@@ -57,6 +59,8 @@ function(add_board_target BOARD_TARGET)
       )
     target_link_options(${BOARD_TARGET} PUBLIC
       "LINKER:--script=${LD_FILE_GNU}"
+      -Wl,--defsym=__flash_size=${LD_FLASH_SIZE}
+      -Wl,--defsym=__ram_size=${LD_RAM_SIZE}
       -nostartfiles
       --specs=nosys.specs --specs=nano.specs
       )
diff --git a/hw/bsp/ch32v20x/family.mk b/hw/bsp/ch32v20x/family.mk
index 7e290bb18..6b09fdac7 100644
--- a/hw/bsp/ch32v20x/family.mk
+++ b/hw/bsp/ch32v20x/family.mk
@@ -7,12 +7,9 @@
 # Toolchain from https://github.com/xpack-dev-tools/riscv-none-elf-gcc-xpack
 CROSS_COMPILE ?= riscv-none-elf-
 
-# Submodules
-CH32V20X_SDK = hw/mcu/wch/ch32v20x
-DEPS_SUBMODULES += $(CH32V20X_SDK)
-
-# WCH-SDK paths
-CH32V20X_SDK_SRC = $(CH32V20X_SDK)/EVT/EXAM/SRC
+CH32_FAMILY = ch32v20x
+SDK_DIR = hw/mcu/wch/ch32v20x
+SDK_SRC_DIR = $(SDK_DIR)/EVT/EXAM/SRC
 
 include $(TOP)/$(BOARD_PATH)/board.mk
 CPU_CORE ?= rv32imac-ilp32
@@ -23,27 +20,29 @@ CFLAGS += \
 	-fdata-sections \
 	-ffat-lto-objects \
 	-flto \
+	-DCH32V20x_${MCU_VARIANT} \
 	-DCFG_TUSB_MCU=OPT_MCU_CH32V20X \
 	-DBOARD_TUD_MAX_SPEED=OPT_MODE_FULL_SPEED \
 
 LDFLAGS_GCC += \
-	-Wl,--gc-sections \
 	-nostdlib -nostartfiles \
 	--specs=nosys.specs --specs=nano.specs \
 
-LD_FILE = $(CH32V20X_SDK_SRC)/Ld/Link.ld
+LD_FILE = $(FAMILY_PATH)/linker/${CH32_FAMILY}.ld
 
 SRC_C += \
 	src/portable/wch/dcd_ch32_usbfs.c \
-	$(CH32V20X_SDK_SRC)/Core/core_riscv.c \
-	$(CH32V20X_SDK_SRC)/Peripheral/src/ch32v20x_gpio.c \
-	$(CH32V20X_SDK_SRC)/Peripheral/src/ch32v20x_misc.c \
-	$(CH32V20X_SDK_SRC)/Peripheral/src/ch32v20x_rcc.c \
-	$(CH32V20X_SDK_SRC)/Peripheral/src/ch32v20x_usart.c \
+	$(SDK_SRC_DIR)/Core/core_riscv.c \
+	$(SDK_SRC_DIR)/Peripheral/src/ch32v20x_gpio.c \
+	$(SDK_SRC_DIR)/Peripheral/src/ch32v20x_misc.c \
+	$(SDK_SRC_DIR)/Peripheral/src/ch32v20x_rcc.c \
+	$(SDK_SRC_DIR)/Peripheral/src/ch32v20x_usart.c \
+
+SRC_S += $(SDK_SRC_DIR)/Startup/startup_ch32v20x_${MCU_VARIANT}.S
 
 INC += \
 	$(TOP)/$(BOARD_PATH) \
-	$(TOP)/$(CH32V20X_SDK_SRC)/Peripheral/inc \
+	$(TOP)/$(SDK_SRC_DIR)/Peripheral/inc \
 
 FREERTOS_PORTABLE_SRC = $(FREERTOS_PORTABLE_PATH)/RISC-V
 
diff --git a/hw/bsp/ch32v20x/linker/ch32v20x.ld b/hw/bsp/ch32v20x/linker/ch32v20x.ld
new file mode 100644
index 000000000..6ee2fa1c7
--- /dev/null
+++ b/hw/bsp/ch32v20x/linker/ch32v20x.ld
@@ -0,0 +1 @@
+/* Define default values if not already defined */
__FLASH_SIZE = DEFINED(__flash_size) ? __flash_size : 64K;
__RAM_SIZE = DEFINED(__ram_size) ? __ram_size : 20K;

MEMORY
{
	FLASH (rx) : ORIGIN = 0x00000000, LENGTH = __FLASH_SIZE
	RAM (xrw) : ORIGIN = 0x20000000, LENGTH = __RAM_SIZE
}

ENTRY( _start )

__stack_size = 2048;

PROVIDE( _stack_size = __stack_size );

SECTIONS
{

	.init :
	{
		_sinit = .;
		. = ALIGN(4);
		KEEP(*(SORT_NONE(.init)))
		. = ALIGN(4);
		_einit = .;
	} >FLASH AT>FLASH

  .vector :
  {
      *(.vector);
	  . = ALIGN(64);
  } >FLASH AT>FLASH

	.text :
	{
		. = ALIGN(4);
		*(.text)
		*(.text.*)
		*(.rodata)
		*(.rodata*)
		*(.gnu.linkonce.t.*)
		. = ALIGN(4);
	} >FLASH AT>FLASH 

	.fini :
	{
		KEEP(*(SORT_NONE(.fini)))
		. = ALIGN(4);
	} >FLASH AT>FLASH

	PROVIDE( _etext = . );
	PROVIDE( _eitcm = . );	

	.preinit_array  :
	{
	  PROVIDE_HIDDEN (__preinit_array_start = .);
	  KEEP (*(.preinit_array))
	  PROVIDE_HIDDEN (__preinit_array_end = .);
	} >FLASH AT>FLASH 
	
	.init_array     :
	{
	  PROVIDE_HIDDEN (__init_array_start = .);
	  KEEP (*(SORT_BY_INIT_PRIORITY(.init_array.*) SORT_BY_INIT_PRIORITY(.ctors.*)))
	  KEEP (*(.init_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .ctors))
	  PROVIDE_HIDDEN (__init_array_end = .);
	} >FLASH AT>FLASH 
	
	.fini_array     :
	{
	  PROVIDE_HIDDEN (__fini_array_start = .);
	  KEEP (*(SORT_BY_INIT_PRIORITY(.fini_array.*) SORT_BY_INIT_PRIORITY(.dtors.*)))
	  KEEP (*(.fini_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .dtors))
	  PROVIDE_HIDDEN (__fini_array_end = .);
	} >FLASH AT>FLASH 
	
	.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
	     doesn't matter which directory crtbegin.o
	     is in.  */
	  KEEP (*crtbegin.o(.ctors))
	  KEEP (*crtbegin?.o(.ctors))
	  /* We don't want to include the .ctor section 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 *crtend?.o ) .ctors))
	  KEEP (*(SORT(.ctors.*)))
	  KEEP (*(.ctors))
	} >FLASH AT>FLASH 
	
	.dtors          :
	{
	  KEEP (*crtbegin.o(.dtors))
	  KEEP (*crtbegin?.o(.dtors))
	  KEEP (*(EXCLUDE_FILE (*crtend.o *crtend?.o ) .dtors))
	  KEEP (*(SORT(.dtors.*)))
	  KEEP (*(.dtors))
	} >FLASH AT>FLASH 

	.dalign :
	{
		. = ALIGN(4);
		PROVIDE(_data_vma = .);
	} >RAM AT>FLASH	

	.dlalign :
	{
		. = ALIGN(4); 
		PROVIDE(_data_lma = .);
	} >FLASH AT>FLASH

	.data :
	{
    	*(.gnu.linkonce.r.*)
    	*(.data .data.*)
    	*(.gnu.linkonce.d.*)
		. = ALIGN(8);
    	PROVIDE( __global_pointer$ = . + 0x800 );
    	*(.sdata .sdata.*)
		*(.sdata2.*)
    	*(.gnu.linkonce.s.*)
    	. = ALIGN(8);
    	*(.srodata.cst16)
    	*(.srodata.cst8)
    	*(.srodata.cst4)
    	*(.srodata.cst2)
    	*(.srodata .srodata.*)
    	. = ALIGN(4);
		PROVIDE( _edata = .);
	} >RAM AT>FLASH

	.bss :
	{
		. = ALIGN(4);
		PROVIDE( _sbss = .);
  	    *(.sbss*)
        *(.gnu.linkonce.sb.*)
		*(.bss*)
     	*(.gnu.linkonce.b.*)		
		*(COMMON*)
		. = ALIGN(4);
		PROVIDE( _ebss = .);
	} >RAM AT>FLASH

	PROVIDE( _end = _ebss);
	PROVIDE( end = . );

    .stack ORIGIN(RAM) + LENGTH(RAM) - __stack_size :
    {
        PROVIDE( _heap_end = . );   
        . = ALIGN(4);
        PROVIDE(_susrstack = . );
        . = . + __stack_size;
        PROVIDE( _eusrstack = .);
    } >RAM 

}