On floppy disks, the address field list consists of a series of 4-byte entries, one entry per sector, in the following format:Initializes disk sector and track address fields on the specified track.
Call with:
AH = 05H
AL = interleave (PC/XT fixed disks)
CH = cylinder
DH = head
DL = drive
00H—7FH floppy disk
80H—FFH fixed disk
ES:BX = segment:offset of address field list (except PC/XT fixed
disk, see Note)
Returns:
If function successful
Carry flag = clear
AH = 00H
If function unsuccessful
Carry flag = set
AH = status (see Int 13H Function 01H)
Notes:
On floppy disks, the address field list consists of a series of 4-byte entries, one entry per sector, in the following format:
Byte(s) Contents 0 cylinder 1 head 2 sector 3 sector-size code
00H if 128 bytes per sector 01H if 256 bytes per sector 02H if 512 bytes per sector (standard) 03H if 1024 bytes per sector
On floppy disks, the number of sectors per track is taken from the BIOS floppy disk parameter table whose address is stored in the vector for Int 1EH.
When this function is used for floppy disks on the PC/AT or PS/2, it should be preceded by a call to Int 13H Function 17H to select the type of medium to be formatted.
On fixed disks, the upper 2 bits of the 10-bit cylinder number are placed in the upper 2 bits of register CL.
On PC/XT-286, PC/AT, and PS/2 fixed disks, ES:BX points to a 512-byte buffer containing byte pairs for each physical disk sector, as follows:
Byte(s) Contents 0 00H for good sector 80H for bad sector 1 sector number
For example, to format a track with 17 sectors and an interleave of two, ES:BX would point to the following 34-byte array at the beginning of a 512-byte buffer:
db 00h,01h,00h,0ah,00h,02h,00h,0bh,00h,03h,00h,0ch
db 00h,04h,00h,0dh,00h,05h,00h,0eh,00h,06h,00h,0fh
db 00h,07h,00h,10h,00h,08h,00h,11h,00h,09h