Manual

220 Series Commercial Grade CF Product Manual v2.0Cactus Technologies
®
30
This register contains the low order 8 bits of the starting cylinder address or bits 15-8 of the
Logical Block Address.
This register contains the high order bits of the starting cylinder address or bits 23-16 of the
Logical Block Address.
The Drive/Head register is used to select the drive and head. It is also used to select LBA
addressing instead of cylinder/head/sector addressing. The bits are dened as follows:
4.5.6. Cylinder Low
(LBA 15-8) Register (Address—1F4[174]; Oset 4)
4.5.7. Cylinder High (LBA 23-16) Register
(LBA 23-16) Register (Address—1F5[175]; Oset 5)
4.5.8. Drive/Head
(LBA 27-24) Register (Address 1F6[176]; Oset 6)
D7 D6 D5 D4 D3 D2 D1 D0
1 LBA 1 DRV HS3 HS2 HS1 HS0
Bit 7 This bit is set to 1.
Bit 6 LBA is a ag to select either Cylinder/Head/Sector (CHS) or Logical Block Address
Mode (LBA). When LBA=0, Cylinder/Head/Sector mode is selected. When LBA=1,
Logical Block Address is selected. In Logical Block Mode, the Logical Block
Address is interpreted as follows:
LBA07-LBA00: Sector Number Register D7-D0.
LBA15-LBA08: Cylinder Low Register D7-D0.
LBA23-LBA16: Cylinder High Register D7-D0.
LBA27-LBA24: Drive/Head Register bits HS3-HS0.
Bit 5 This bit is set to 1.
Bit 4 (DRV) This bit will have the following meaning. DRV is the drive number. When DRV=0,
drive (card) 0 is selected When DRV=1, drive (card) 1 is selected. In PCMCIA
Mode operation, Card 0 or 1 is selected using the copy eld of the PC Card
Socket and Copy conguration register.
Bit 3 (HS3) When operating in the Cylinder, Head, Sector mode, this is bit 3 of the head
number. It is Bit 27 in the Logical Block Address mode.
Bit 2 (HS2) When operating in the Cylinder, Head, Sector mode, this is bit 2 of the head
number. It is Bit 26 in the Logical Block Address mode.
Bit 1 (HS1) When operating in the Cylinder, Head, Sector mode, this is bit 1 of the head
number. It is Bit 25 in the Logical Block Address mode.
Bit 0 (HS0) When operating in the Cylinder, Head, Sector mode, this is bit 0 of the head
number. It is Bit 24 in the Logical Block Address mode.