INT 13,5 - Format Disk Track
AH = 05 AL = interleave value (XT only) CX = track/cylinder number (see below for format) DH = head number (0-15 dec.) DL = drive number (0=A:, 1=2nd floppy, 80h=drive 0, 81h=drive 1) ES:BX = pointer to block of "track address fields" containing four byte fields for each sector to be formatted of the form: 1 byte track number 1 byte head number Size # 1 byte sector number Codes Bytes 1 byte sector size code 0 128 1 256 2 512 3 1024 on return: AH = status (see INT 13,STATUS) CF = 0 if successful = 1 if error - BIOS disk write attempts should reset the controller on error - INT 13,17 should be called to set the DASD type - this function is capable of doing great damage if the parameters are incorrectly specified; only the drive number is checked - initializes disk address fields and data sectors - interleave is specified by ordering of track address fields - after INT 13 disk format, if the disk is to be used with DOS the DOS data structure must be written - only the disk number is checked for validity - the parameters in CX change depending on the number of cylinders; the track/cylinder number is a 10 bit value taken from the 2 high order bits of CL and the 8 bits in CH (low order 8 bits of track): │F│E│D│C│B│A│9│8│7│6│5-0│ CX (cylinder value 0-1023 dec.) │ │ │ │ │ │ │ │ │ │ └───── unused │ │ │ │ │ │ │ │ └─┴─────── high order 2 bits of track/cylinder └─┴─┴─┴─┴─┴─┴─┴────────── low order 8 bits of track/cyl number