Int 13H [AT] [PS/2] Function 18H (24) Set media type for format

Selects media characteristics for the specified drive.

Call with:

AH = 18H

CH = number of cylinders

CL = sectors per track

DL = drive

00H—7FH floppy disk

Returns:

If function successful

Carry flag = clear

AH = 00H

ES:DI = segment:offset of disk parameter table for media type

If function unsuccessful

Carry flag = set

AH = status (see Int 13H Function 01H)

Notes:

A floppy disk must be present in the drive.

This function should be called prior to formatting a disk with Int 13H Function 05H so that the ROM BIOS can set the correct data rate for the media.

If the change line is active for the specified drive, it is reset.