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