Function 53h "Used Internally by DOS" - Translate BPB
* Translates BPB (BIOS Parameter Block, see below) into a DOS Disk
Block (see function call 32h).
entry AH 53h
DS:SI pointer to BPB
ES:BP pointer to area for DOS Disk Block.
Layout of Disk Block:
bytes value
00h-01h bytes per sector, get from DDB bytes 02h-03h.
02h sectors per cluster, get from (DDB byte 4) + 1
03h-04h reserved sectors, get from DDB bytes 06h-07h
05h number of FATs, get from DDB byte 08h
06h-07h number of root dir entries, get from DDB bytes 09h-0Ah
08h-09h total number of sectors, get from:
((DDB bytes 0Dh-0Eh) - 1) * (sectors per cluster (BPB
byte 2)) + (DDB bytes 0Bh-0Ch)
0Ah media descriptor byte, get from DDB byte 16h
0Bh-0Ch number of sectors per FAT, get from DDB byte 0Fh
return unknown
file: /Techref/INT/21f/53.htm, 1KB, , updated: 1999/2/20 10:26, local time: 2024/11/27 16:59,
18.188.132.71:LOG IN
|
©2024 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions? <A HREF="http://ecomorder.com/techref/INT/21f/53.htm"> INT 21f 53</A> |
Did you find what you needed? |
Welcome to ecomorder.com! |
Welcome to ecomorder.com! |
.