diag/geodsp/README: Additional use notes

diff --git a/diag/geodsp/README b/diag/geodsp/README
index 43a3edc..55e0843 100644 (file)
--- a/diag/geodsp/README
+++ b/diag/geodsp/README
@@ -3,3 +3,9 @@ GeoDsp: Images to display the geometry as the BIOS has choosen to interpret it.
 GeoDsp1S is a one-sector variant containing all code in one sector that is intended to test behavior with a typical MBR/partition table layout.  A partition table should be written after writting an image.
 
 GeoDspMS is a multi sector variant intended to look like Syslinux installed on a file system on the raw device (as opposed to a file system within a partition).
+
+GeoDspMS can also be used to attempt to make the boot sector look like a normal file system's boot sector (ie FAT12/FAT16/FAT32).  In order to do this, you must first save a portion the existing boot sector (the majority of the BIOS parameter block).
+       dd bs=1 skip=3 count=87 if=/dev/sda of=sda.bpb
+       dd conv=notrunc if=geodspms.img of=/dev/sda
+       dd conv=notrunc bs=1 seek=3 count=87 if=sda.bpb of=/dev/sda
+