HDD GURU FORUMS :: View topic

sector 0 was the NTFS boot sector & not the MBR?

loki wrote:

sector 0 was the NTFS boot sector & not the MBR?

That's the "superfloppy format" - no MBR, the PBS starts at sector 0.

Thank you Vulcan for your reply

Think that the partition style showing Master Boot Record throw me as I then expected an MBR

I have seen a case (Akai MPC2000) which had both a BIOS Parameter Block and an MBR style partition table in sector 0. The information in the partition table pointed to sector 0 as the location of the boot sector. The drive was not intended to be bootable. In fact IIRC the first JUMP instruction was a JMP 00, so that would result in an endless loop.

Author:	loki [ December 12th, 2012, 12:37 ]
Post subject:	Strange?
I have been mucking around (with Winhex) on some hard drives & USB pens manually repairing FAT & NTFS boot sectors from back up, zeroing sector 0 & manually redoing the partiton info in the MBR Templates, recovering from diskpart & the clean command (not clean all ) etc just for fun & to understand more. I have a 64Gb USB3 pen which works fines, no issues at all. Thought I'd look at the sector 0 & NTFS boot sectors with winhex but found that sector 0 was the NTFS boot sector & not the MBR? Im use to seeing sector 0 with MBR or zero'd out but with 55AA at the end. As you can see from the pics Attachment: 1.png [ 192.12 KiB \| Viewed 8264 times ] Attachment: 2.png [ 108.03 KiB \| Viewed 8264 times ] Attachment: 3.png [ 65.92 KiB \| Viewed 8264 times ] Loki

Author:	Vulcan [ December 12th, 2012, 12:59 ]
Post subject:	Re: Strange?
loki wrote: sector 0 was the NTFS boot sector & not the MBR? That's the "superfloppy format" - no MBR, the PBS starts at sector 0.

Author:	loki [ December 12th, 2012, 13:19 ]
Post subject:	Re: Strange?
Vulcan wrote: loki wrote: sector 0 was the NTFS boot sector & not the MBR? That's the "superfloppy format" - no MBR, the PBS starts at sector 0. Thank you Vulcan for your reply Something else for me to learn & research Loki

Author:	loki [ December 12th, 2012, 13:47 ]
Post subject:	Re: Strange?
Think that the partition style showing Master Boot Record throw me as I then expected an MBR Attachment: pic.png [ 31.64 KiB \| Viewed 8246 times ] Loki

Author:	Vulcan [ December 12th, 2012, 18:13 ]
Post subject:	Re: Strange?
loki wrote: Thank you Vulcan for your reply You're very welcome, Loki loki wrote: Think that the partition style showing Master Boot Record throw me as I then expected an MBR I see what you mean. Good old Windows

HDD GURU FORUMS http://forum.hddguru.com/

Strange? http://forum.hddguru.com/viewtopic.php?f=10&t=24708	Page 1 of 1

Author:	fzabkar [ April 14th, 2013, 5:56 ]
Post subject:	Re: Strange?
I have seen a case (Akai MPC2000) which had both a BIOS Parameter Block and an MBR style partition table in sector 0. The information in the partition table pointed to sector 0 as the location of the boot sector. The drive was not intended to be bootable. In fact IIRC the first JUMP instruction was a JMP 00, so that would result in an endless loop.

Author:	fzabkar [ April 17th, 2013, 16:58 ]
Post subject:	Re: Strange?
fzabkar wrote: I have seen a case (Akai MPC2000) which had both a BIOS Parameter Block and an MBR style partition table in sector 0. The information in the partition table pointed to sector 0 as the location of the boot sector. The drive was not intended to be bootable. In fact IIRC the first JUMP instruction was a JMP 00, so that would result in an endless loop. Here it is: http://www.users.on.net/~fzabkar/MPC2000_mbr.txt Code: C:\>debug -e 100 EB FE 90 -u 100 0100 EBFE JMP 0100 0102 90 NOP The drive has been divided into 26 FAT partitions. Their starting sectors are recorded as little endian double words beginning at offset 0x40. 0x00000000 0x00053919 0x000A7232 ... 0x00829371

Page 1 of 1	All times are UTC - 5 hours [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group http://www.phpbb.com/