diff --git a/Code/pico_multi_booter/applink.py b/Code/pico_multi_booter/applink.py
index 07d66ee..7973604 100644
--- a/Code/pico_multi_booter/applink.py
+++ b/Code/pico_multi_booter/applink.py
@@ -463,12 +463,20 @@ def Built(dir, app):
         if adr + length - 1 > last : last = adr + length - 1
       block = Uf2Block(f)
 
+##enlarge sd_boot flash size
+  if app == "sd_boot":
+    print("original last: ", last," ",'{:02X}'.format(last))
+    print("orignal size: ","{:>3}k".format(Size(last-strt, 1024)))
+    print("orignal used: ","{:>3}k".format(Size(last, 4*1024)))
+    if last < 0x10032000:
+      last = 0x10032000
+
   size = "{:>3}k".format(Size(last-strt, 1024))
   used = "{:>3}k".format(Size(last, 4*1024))
   
   print(last,strt) 
   print(size,used)
-    
+ 
   mapfile = os.path.join(dir, "applink.map")
   if (strt & 0x0FFFFFFF) == 0:
     with open(mapfile, "w") as f:
diff --git a/Code/pico_multi_booter/linker_scripts/memmap_default.ld.mp.rp2040 b/Code/pico_multi_booter/linker_scripts/memmap_default.ld.mp.rp2040
index 25817b3..f0251d5 100644
--- a/Code/pico_multi_booter/linker_scripts/memmap_default.ld.mp.rp2040
+++ b/Code/pico_multi_booter/linker_scripts/memmap_default.ld.mp.rp2040
@@ -1,7 +1,7 @@
 /*arduino-pico*/
 MEMORY
 {
-    FLASH(rx) : ORIGIN = 0x10000000 + 152k, LENGTH = __FLASH_LENGTH__ - 152k
+    FLASH(rx) : ORIGIN = 0x10000000 + 200k, LENGTH = __FLASH_LENGTH__ - 200k
     RAM(rwx) : ORIGIN =  0x20000000, LENGTH = __RAM_LENGTH__
     SCRATCH_X(rwx) : ORIGIN = 0x20040000, LENGTH = 4k
     SCRATCH_Y(rwx) : ORIGIN = 0x20041000, LENGTH = 4k
diff --git a/Code/pico_multi_booter/linker_scripts/memmap_mp_rp2040.ld b/Code/pico_multi_booter/linker_scripts/memmap_mp_rp2040.ld
index c453adb..1905bf3 100644
--- a/Code/pico_multi_booter/linker_scripts/memmap_mp_rp2040.ld
+++ b/Code/pico_multi_booter/linker_scripts/memmap_mp_rp2040.ld
@@ -24,7 +24,7 @@
 
 MEMORY
 {
-    FLASH(rx) : ORIGIN = 0x10000000 + 152k, LENGTH = 2048k - 152k
+    FLASH(rx) : ORIGIN = 0x10000000 + 200k, LENGTH = 2048k - 200k
     RAM(rwx) : ORIGIN =  0x20000000, LENGTH = 256k
     SCRATCH_X(rwx) : ORIGIN = 0x20040000, LENGTH = 4k
     SCRATCH_Y(rwx) : ORIGIN = 0x20041000, LENGTH = 4k
diff --git a/Code/pico_multi_booter/linker_scripts/rpi-pico.ld b/Code/pico_multi_booter/linker_scripts/rpi-pico.ld
index c8da485..2a2b595 100644
--- a/Code/pico_multi_booter/linker_scripts/rpi-pico.ld
+++ b/Code/pico_multi_booter/linker_scripts/rpi-pico.ld
@@ -4,7 +4,7 @@
 
 MEMORY
 {
-    FLASH(rx)      : ORIGIN = 0x10000000 + 152k, LENGTH = 2048k - 152k
+    FLASH(rx)      : ORIGIN = 0x10000000 + 200k, LENGTH = 2048k - 200k
     RAM(rwx)       : ORIGIN = 0x20000000, LENGTH = 256k
     SCRATCH_X(rwx) : ORIGIN = 0x20040000, LENGTH = 4k
     SCRATCH_Y(rwx) : ORIGIN = 0x20041000, LENGTH = 4k
diff --git a/Code/pico_multi_booter/memmap_default_rp2040.ld b/Code/pico_multi_booter/memmap_default_rp2040.ld
index 3c5ab0c..31efe94 100644
--- a/Code/pico_multi_booter/memmap_default_rp2040.ld
+++ b/Code/pico_multi_booter/memmap_default_rp2040.ld
@@ -1,6 +1,6 @@
 MEMORY
 {
-    FLASH(rx) : ORIGIN = 0x10000000 + 152k, LENGTH = 2048k - 152k
+    FLASH(rx) : ORIGIN = 0x10000000 + 200k, LENGTH = 2048k - 200k
     RAM(rwx) : ORIGIN =  0x20000000, LENGTH = 256k
     SCRATCH_X(rwx) : ORIGIN = 0x20040000, LENGTH = 4k
     SCRATCH_Y(rwx) : ORIGIN = 0x20041000, LENGTH = 4k
diff --git a/Code/pico_multi_booter/memmap_default_rp2350.ld b/Code/pico_multi_booter/memmap_default_rp2350.ld
index 6f8d4c4..949a391 100644
--- a/Code/pico_multi_booter/memmap_default_rp2350.ld
+++ b/Code/pico_multi_booter/memmap_default_rp2350.ld
@@ -23,7 +23,7 @@
 
 MEMORY
 {
-    FLASH(rx) : ORIGIN = 0x10000000 + 152k, LENGTH = 4096k - 152k
+    FLASH(rx) : ORIGIN = 0x10000000 + 200k, LENGTH = 4096k - 200k
     RAM(rwx) : ORIGIN =  0x20000000, LENGTH = 512k
     SCRATCH_X(rwx) : ORIGIN = 0x20080000, LENGTH = 4k
     SCRATCH_Y(rwx) : ORIGIN = 0x20081000, LENGTH = 4k
diff --git a/Code/pico_multi_booter/picomite/configuration.h b/Code/pico_multi_booter/picomite/configuration.h
index 08b7dac..03d2e76 100644
--- a/Code/pico_multi_booter/picomite/configuration.h
+++ b/Code/pico_multi_booter/picomite/configuration.h
@@ -162,7 +162,7 @@ extern "C" {
     #ifdef rp2350
         #define HEAP_MEMORY_SIZE (288*1024) 
         #define MAXVARS             768                     // 8 + MAXVARLEN + MAXDIM * 4  (ie, 64 bytes) - these do not incl array members
-        #define FLASH_TARGET_OFFSET (920 * 1024) 
+        #define FLASH_TARGET_OFFSET (968 * 1024) 
         #define MAX_CPU     (rp2350a ? 396000 : 378000)
         #define MAXSUBFUN           512                     // each entry takes up 4 bytes
         #ifdef USBKEYBOARD
@@ -175,7 +175,7 @@ extern "C" {
     #else
         #define HEAP_MEMORY_SIZE (128*1024) 
         #define MAXVARS             512                     // 8 + MAXVARLEN + MAXDIM * 2  (ie, 56 bytes) - these do not incl array members
-        #define FLASH_TARGET_OFFSET (920 * 1024) 
+        #define FLASH_TARGET_OFFSET (968 * 1024) 
         #define MAX_CPU     420000
         #define MAXSUBFUN           256                     // each entry takes up 4 bytes
         #ifdef USBKEYBOARD
diff --git a/Code/pico_multi_booter/sd_boot/config.h b/Code/pico_multi_booter/sd_boot/config.h
index 16cd24c..c7ddd23 100644
--- a/Code/pico_multi_booter/sd_boot/config.h
+++ b/Code/pico_multi_booter/sd_boot/config.h
@@ -36,7 +36,7 @@
 // According to the applink.map ,with combined PicoMite, here is 920k
 // This offset is used to ensure that the bootloader does not get overwritten
 // when loading a new application from the SD card
-#define SD_BOOT_FLASH_OFFSET         (152 * 1024)
+#define SD_BOOT_FLASH_OFFSET         (200 * 1024)
 
 // Maximum size of the application that can be loaded
 // This ensures we don't overwrite the bootloader itself