diff --git a/arch/sim/src/up_deviceimage.c b/arch/sim/src/up_deviceimage.c
index 46c42792fc..7484240d07 100644
--- a/arch/sim/src/up_deviceimage.c
+++ b/arch/sim/src/up_deviceimage.c
@@ -72,41 +72,59 @@
 
 /* This array holds a compressed VFAT file system created with:
  *
- * /sbin/mkdosfs -C -F 32 -I -n "NuttXTestVol" -s 4 -S 512 
- *    -v nuttx-test.vfat 1024
+ *   /sbin/mkdosfs -C -F 32 -I -n "NuttXTestVol" -S 512 -v nuttx-test.vfat 1024
+ *   sudo mkdir /mnt/loop
+ *   sudo mount -o loop nuttx-test.vfat /mnt/loop
+ *   mkdir /mnt/loop/nuttx-test
+ *   echo "This is a test" >/mnt/loop/nuttx-test/test-file.txt
+ *   sudo umount /mnt/loop
+ *   gzip nuttx-test.vfat
+ *   xxd -g 1 nuttx-test.vfat.gz >some-file
  *
- * Then manually massaged from gzip to zlib format
+ * Then manually massaged from the gzip xxd output to zlib format.  See
+ * http://www.faqs.org/rfcs/rfc1952.html
  */
 
 static const unsigned char g_vfatdata[] =
 {
-    0x08, 0x1d, 0xed, 0xdc, 0x31, 0x6b, 0x53, 0x51, 0x14, 0x07, 0xf0, 0xdb,
-    0x52, 0xb4, 0x54, 0x5a, 0x9d, 0x04, 0x27, 0x0f, 0x6e, 0x2e, 0x19, 0x2a,
-    0x74, 0x13, 0xcc, 0x60, 0x47, 0x91, 0x92, 0x96, 0x4e, 0xc2, 0x2b, 0x79,
-    0xd5, 0x90, 0x98, 0x17, 0xde, 0x7b, 0x22, 0x01, 0x77, 0x47, 0xfd, 0x18,
-    0x52, 0x32, 0xba, 0x09, 0xe2, 0x17, 0xc8, 0xb7, 0x70, 0xcb, 0xd2, 0xa5,
-    0xd0, 0xc9, 0x98, 0x52, 0x05, 0x33, 0xb9, 0xa8, 0x4f, 0xe8, 0xef, 0xc7,
-    0xbd, 0x9c, 0x0b, 0x67, 0xf9, 0x2f, 0x97, 0x7b, 0xa6, 0x3b, 0x3b, 0x7c,
-    0xff, 0xb2, 0xdf, 0x2d, 0xaa, 0xe3, 0x2a, 0xa5, 0xd5, 0xb5, 0x48, 0xab,
-    0x29, 0xa5, 0xf5, 0xf3, 0x94, 0x22, 0x3d, 0x4a, 0x3f, 0xad, 0xfd, 0xa8,
-    0x17, 0xbd, 0x95, 0x74, 0x2d, 0x2d, 0xbb, 0xff, 0xee, 0xc3, 0xe3, 0xdd,
-    0x27, 0xaf, 0xea, 0xfa, 0xb0, 0x93, 0x57, 0xf5, 0x41, 0xb1, 0xdb, 0xee,
-    0x3c, 0xd8, 0x8e, 0x88, 0xad, 0xbb, 0x9f, 0x5f, 0xbf, 0x99, 0xdc, 0xfb,
-    0x52, 0xdf, 0x38, 0xf8, 0xb8, 0xf5, 0xe9, 0x7a, 0x9a, 0xde, 0x7a, 0x36,
-    0x3b, 0xdd, 0xfe, 0x3a, 0xbd, 0x3d, 0xbd, 0x33, 0xfb, 0xd6, 0x79, 0xd1,
-    0xab, 0x62, 0xb1, 0x86, 0x45, 0x1d, 0x59, 0x1c, 0x15, 0x45, 0x9d, 0x1d,
-    0x0d, 0xf2, 0xe8, 0xf6, 0xaa, 0x7e, 0x2b, 0xe2, 0xe9, 0x20, 0xcf, 0xaa,
-    0x3c, 0x7a, 0xc3, 0x2a, 0x2f, 0x97, 0xfa, 0xc7, 0x83, 0x62, 0x34, 0x1a,
-    0x47, 0x36, 0xec, 0x6e, 0x6e, 0x8c, 0xca, 0xbc, 0xaa, 0x16, 0xc7, 0x71,
-    0xf4, 0xf3, 0x71, 0xd4, 0x45, 0xd4, 0xe5, 0xa2, 0xf3, 0x3c, 0xeb, 0x0d,
-    0xa3, 0xd5, 0x6a, 0xc5, 0xe6, 0x46, 0xe2, 0x77, 0xf6, 0x4f, 0xf6, 0xf6,
-    0xb2, 0x76, 0xd3, 0x29, 0xf8, 0xbb, 0xca, 0xb2, 0x9d, 0x9d, 0xad, 0x5c,
-    0xde, 0xdf, 0x65, 0xfb, 0x27, 0x0d, 0xc4, 0x01, 0x00, 0x1a, 0x36, 0x33,
-    0xff, 0x5f, 0x61, 0xe6, 0x3f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-    0x00, 0x00, 0x00, 0x00, 0x80, 0xff, 0xdd, 0xf9, 0x7c, 0x7e, 0x73, 0xbe,
-    0xd8, 0x17, 0xb5, 0xe9, 0x2c, 0x00, 0xc0, 0xbf, 0xe1, 0xfd, 0x07, 0x80,
-    0xab, 0xe7, 0x97, 0x8f, 0x3b, 0xd6, 0x53, 0x7a, 0xfb, 0x70, 0xb2, 0x33,
-    0xd9, 0xb9, 0xac, 0x4d, 0x27, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x08, 0x1d, 0xed, 0xdd, 0x4d, 0x6b, 0x13, 0x41, 0x18, 0x00, 0xe0, 0x69,
+    0x2d, 0xb6, 0x54, 0xfa, 0x71, 0x12, 0x3c, 0x39, 0x78, 0x53, 0x48, 0xa0,
+    0x55, 0x7a, 0x36, 0x07, 0xab, 0xa7, 0x22, 0x75, 0x5b, 0x72, 0x12, 0x52,
+    0x92, 0x6a, 0x68, 0x4c, 0x4a, 0x76, 0x8b, 0x2d, 0x48, 0x6f, 0xbd, 0xfb,
+    0x2f, 0xc4, 0x62, 0x4f, 0x7a, 0x13, 0xc5, 0x3f, 0x90, 0x7f, 0xe1, 0x2d,
+    0x97, 0x1e, 0x7b, 0x32, 0x6e, 0x4c, 0x53, 0x2c, 0x22, 0x7e, 0x80, 0x44,
+    0xf1, 0x79, 0x76, 0x67, 0x66, 0xd9, 0x97, 0x81, 0x59, 0xe6, 0x65, 0x19,
+    0xd8, 0x85, 0xe9, 0x96, 0x9f, 0x3f, 0xd9, 0xaa, 0xb6, 0xd2, 0xcd, 0x34,
+    0x84, 0xf1, 0xb1, 0x18, 0xc6, 0x43, 0x08, 0x53, 0x27, 0x21, 0xc4, 0x70,
+    0x3b, 0x0c, 0xcd, 0x9f, 0xb6, 0xfd, 0xd8, 0x58, 0xb8, 0x18, 0xce, 0xbb,
+    0x7e, 0xfc, 0xfa, 0xee, 0xf2, 0xca, 0x4e, 0x96, 0x95, 0x93, 0x5a, 0x9a,
+    0xad, 0xb7, 0x96, 0x4b, 0xc9, 0xcd, 0xc5, 0x18, 0xe3, 0xec, 0xd5, 0xf7,
+    0x4f, 0x9f, 0xbd, 0xba, 0xf6, 0x21, 0xbb, 0xb4, 0xfe, 0x66, 0xf6, 0xed,
+    0x64, 0xe8, 0xcc, 0x3f, 0xec, 0x1e, 0x2f, 0x7e, 0xec, 0x5c, 0xee, 0x5c,
+    0xe9, 0x7e, 0x4a, 0x1e, 0xd7, 0xd3, 0x98, 0x9f, 0xcd, 0x56, 0x16, 0x2b,
+    0x71, 0xa3, 0xd5, 0xca, 0x2a, 0x1b, 0x8d, 0x5a, 0xac, 0xd6, 0xd3, 0xad,
+    0x62, 0x8c, 0xf7, 0x1b, 0xb5, 0x4a, 0x5a, 0x8b, 0xf5, 0x66, 0x5a, 0x6b,
+    0x9f, 0x8b, 0x6f, 0x36, 0x5a, 0xdb, 0xdb, 0x7b, 0xb1, 0xd2, 0xac, 0xce,
+    0x4c, 0x6f, 0xb7, 0x6b, 0x69, 0x9a, 0x5f, 0xee, 0xc5, 0xad, 0xda, 0x5e,
+    0xcc, 0x5a, 0x31, 0x6b, 0xe7, 0x91, 0x47, 0x95, 0x7a, 0x33, 0x16, 0x8b,
+    0xc5, 0x38, 0x33, 0x1d, 0xf8, 0x91, 0xb5, 0xc3, 0xd5, 0xd5, 0x4a, 0x69,
+    0xd4, 0xa3, 0xe0, 0xcf, 0x6a, 0xb7, 0x4b, 0x95, 0x77, 0x93, 0x21, 0x4c,
+    0x7c, 0x13, 0x59, 0x3b, 0x1c, 0xc1, 0x70, 0x00, 0x80, 0x11, 0xeb, 0x5a,
+    0xff, 0xff, 0xc7, 0xac, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0xfe, 0x76, 0x27, 0xbd, 0xde, 0x5c, 0x2f,
+    0x2f, 0xc3, 0xb6, 0x5f, 0x46, 0x3d, 0x26, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0xe0, 0xd7, 0xf8, 0xfe, 0x0f, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0xff, 0xbe, 0xaf, 0x36, 0xee, 0x9c, 0x0a, 0xe1, 0xc6, 0x8b,
+    0xa3, 0xa5, 0xa3, 0xa5, 0x41, 0x3b, 0x88, 0x97, 0x9a, 0x61, 0x27, 0x64,
+    0xf9, 0xb1, 0x1b, 0xe6, 0xc2, 0xbd, 0x42, 0x7e, 0x51, 0x0b, 0x69, 0x5e,
+    0xf7, 0xf5, 0x72, 0x2b, 0x6b, 0x49, 0x52, 0x2e, 0xec, 0x2f, 0xc4, 0x18,
+    0xe7, 0x43, 0xb5, 0xf3, 0x72, 0xd0, 0xbf, 0xdf, 0x5e, 0x18, 0xe1, 0x53,
+    0xf1, 0xb3, 0x8a, 0xf1, 0xcc, 0x7c, 0x08, 0x07, 0xa7, 0xf3, 0x77, 0x70,
+    0x36, 0x7f, 0xc5, 0xe2, 0xf7, 0xe2, 0x83, 0xfe, 0xa5, 0x61, 0x42, 0x14,
+    0xf2, 0xfc, 0xb8, 0xb5, 0x19, 0xea, 0xa1, 0x91, 0xdf, 0x28, 0x7e, 0xc9,
+    0x90, 0xdd, 0xbc, 0x4e, 0xee, 0x3c, 0x48, 0x0a, 0xcb, 0xfb, 0x0b, 0x49,
+    0x39, 0x89, 0xe7, 0xf3, 0x63, 0x22, 0xf8, 0xd1, 0x64, 0xf4, 0x86, 0x1b,
+    0xf1, 0x56, 0x62, 0x96, 0xbf, 0x04, 0xec, 0x99, 0x0b, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
@@ -188,10 +206,10 @@ static const unsigned char g_vfatdata[] =
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-    0x00, 0x00, 0x00, 0x00, 0x00, 0xf8, 0x33, 0xbe, 0x03
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf0, 0xbb, 0x3e, 0x03
 };
 
+
 /****************************************************************************
  * Private Functions
  ****************************************************************************/