Strange?

[loki]

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

Loki

[Vulcan]

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

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

[loki]

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

[loki]

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

pic.png (31.64 KiB) Viewed 8239 times

Loki

[Vulcan]

Thank you Vulcan for your reply

You're very welcome, Loki

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

[fzabkar]

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.

[fzabkar]

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