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Ok, I am having troubles working out an algorithm to do this in x86 assembly. So lets say I have the hex DC 0B FD F4 at memory offset :1027, it is little-endian stored of course(so the serial is really f4 fd 0b dc). It is the serial number of the disk. I need to convert the hex to ASCII vaules so that I can print them.

For the digits if I add 30H to them then the become there respective ASCII charachter. But I am kinda lost from there.

I am using this code to get the first sector of the floppy disk:

MOV   AH,02

MOV   AL,01

MOV   CH,00

MOV   CL,01

MOV   DX,0000

LEA    BX,[1000]

INT    13

INT    20

this is a dump of what is retrieved:

0B79:1000  EB 3C 90 4D 53 44 4F 53-35 2E 30 00 02 01 01 00   .<.MSDOS5.0.....

0B79:1010  02 E0 00 40 0B F0 09 00-12 00 02 00 00 00 00 00   ...@............

0B79:1020  00 00 00 00 00 00 29 DC-0B FD F4 4E 4F 20 4E 41   ......)....NO NA

0B79:1030  4D 45 20 20 20 20 46 41-54 31 32 20 20 20 33 C9   ME    FAT12   3.

0B79:1040  8E D1 BC F0 7B 8E D9 B8-00 20 8E C0 FC BD 00 7C   ....{.... .....|

0B79:1050  38 4E 24 7D 24 8B C1 99-E8 3C 01 72 1C 83 EB 3A   8N$}$....<.r...:

0B79:1060  66 A1 1C 7C 26 66 3B 07-26 8A 57 FC 75 06 80 CA   f..|&f;.&.W.u...

0B79:1070  02 88 56 02 80 C3 10 73-EB 33 C9 8A 46 10 98 F7   ..V....s.3..F...

down at 0b79:1027 for a lenght of 4bytes is the serial number.

Would someone please help me with a code example or something..

Thanks

Which base do you want it in? Base16 is pretty easy: get a nibble,
use as index to charbuffer, repeat until there's no more nibbles.
Ie, your charbuffer would be "0123456789ABCDEF", and a nibble
is 4 bits. That should be enough hints :).

You can also do as bitrake suggests if you don't mind conditional
jumps, and there's other methods still.