Category: no classification
Flags: Undocumented function
INT 21 - PTS-DOS 6.51 & S/DOS 1.0 - DIRECT DISK WRITE
AH = 91h
CX = FFFFh (for partitions > 32 Mb)
DS:BX -> request block (see #04094)
CX = sector count (for partitions < 32 Mb)
DX = starting sector number
DS:BX -> buffer
Return: CF set on error
AX error code
CF clear on success
Note: This function is supported by Paragon Technology Systems S/DOS 1.0
(and most probably by PTS-DOS 6.51, maybe even earlier).
To access big partitions (> 32 Mb), CX != FFFFh is not allowed and
the buffer must always be used. Otherwise, the system will return
error code 0207h.
It is currently unknown if this function is also supported by
PhysTechSoft PTS-DOS 6.60, 6.70, or 2000.
SeeAlso: INT 21/Ah=90h"PTS",INT 25h,INT 26h