Reads a sector or sectors from disk into memory, along with a 4-byte ECC code for each sector.
Call with:
AH = 0AH
AL = number of sectors
CH = cylinder
CL = sector (see Notes)
DH = head
DL = drive
80H—FFH fixed disk
ES:BX = segment:offset of buffer
Returns:
If function successful
Carry flag = clear
AH = 00H
AL = number of sectors transferred
If function unsuccessful
Carry flag = set
AH = status (see Int 13H Function 01H)
Notes:
This function is supported on fixed disks only.
The upper 2 bits of the 10-bit cylinder number are placed in the upper 2 bits of register CL.
Unlike the normal Read Sector function (Int 13H Function 02H), ECC errors are not automatically corrected. Multisector transfers are terminated after any sector with a read error.