Int 13 Fn 23  U - Hard Disk - Ps/1 And Newer Ps/2 - Set Controller Featur  [d]

   AH = 23h
   AL = feature number (see #0198)
   DL = drive number (80h,81h)
   ???

Return: CF clear if successful
   CF set on error
   AH = status (see #0166 at AH=01h)

See Also: AH=21h"PS/1",AH=22h"PS/1",AH=24h"PS/1",AH=25h"PS/1"

(Table 0198)
Values for PS/1 hard disk feature number:
 01h   select 8-bit data transfers instead of 16-bit
 02h   enable write cache
 22h   Write Same, user-specified area
 33h   disable retries
 44h   set number of ECC bytes for read long/write long (see AH=0Ah,AH=0Bh)
 54h   set cache segments
 55h   disable lookahead
 66h   disable reverting to power-on defaults
 77h   disable error correctioni
 81h   select 16-bit data transfers (default)
 82h   disable write cache
 88h   enable error correction (default)
 99h   enable retries (default)
 AAh   enable lookahead
 BBh   set ECC length for read long/write long to four bytes
 CCh   enable reverting to power-on defaults
 DDh   Write Same, entire disk

See Also: #P175