PORTIBM PC Portable (uses same BIOS as XT) 0320-0323 - XTIBM PC XT HDC 1   (Hard Disk Controller)
SeeAlso: PORTIBM PC Portable (uses same BIOS as XT) 01F0h-01F7h

0320  RW  data register
0321  -W  reset controller
0321  R-  read controller hardware status (see #P0574)
0322  R-  read DIPswitch setting on XTIBM PC XT controller card
0322  -W  generate controller-select pulse
0323  -W  write pattern to DMAsee Direct Memory Access and INT mask register


Bitfields for XTIBM PC XT hard disk controller hardware status:
Bit(s)	Description	(Table P0574)
 7-6	always 0
 5	logical unit number
 4-2	always 0
 1	error occurred
 0	always 0