From a5fef9bb39d2712e17a9e77644a55bfa6ccdc6c9 Mon Sep 17 00:00:00 2001 From: Gene Cumm Date: Sun, 8 Sep 2013 23:22:22 -0400 Subject: [PATCH] diag/geodsp: README fixes Should clarify the situation; also word-wrap & save example Signed-off-by: Gene Cumm --- diag/geodsp/README | 40 +++++++++++++++++++++++++++++----------- 1 file changed, 29 insertions(+), 11 deletions(-) rewrite diag/geodsp/README (74%) diff --git a/diag/geodsp/README b/diag/geodsp/README dissimilarity index 74% index 55e08438..9129b694 100644 --- a/diag/geodsp/README +++ b/diag/geodsp/README @@ -1,11 +1,29 @@ -GeoDsp: Images to display the geometry as the BIOS has choosen to interpret it. Both images are intended to be written to the first ~8MiB of a raw device (ie /dev/hda, /dev/sda) and be over one large cylinder of 255*63 512-byte sectors in size. - -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 - +GeoDsp: Images to display the geometry as the BIOS has choosen to +interpret it. Both images are intended to be written to the first ~8MiB +of a raw device (ie /dev/hda, /dev/sda) and be over one large cylinder +of 255*63 512-byte sectors in size. + +To save the existing data for restore later: + + dd bs=1M iflag=fullblock count=8 if=/dev/sda of=sda.img + +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/sda1 of=sda1.bpb + dd conv=notrunc if=geodspms.img of=/dev/sda1 + dd conv=notrunc bs=1 seek=3 count=87 if=sda1.bpb of=/dev/sda1 + + dd bs=1 skip=3 count=87 if=/dev/fd0 of=fd0.bpb + dd conv=notrunc if=geodspms.img of=/dev/fd0 + dd conv=notrunc bs=1 seek=3 count=87 if=fd0.bpb of=/dev/fd0 -- 2.11.4.GIT