User guide

203 Series Industrial Grade 2.5" FlashDrive Product Manual v2.0Cactus Technologies

4.2.5. Sector Number (LBA 7-0) Register (Address-1F3[173])

This register contains the starting sector number or bits 7-0 of the Logical Block Address (LBA) for

any FlashDrive data access for the subsequent command.

4.2.6. Cylinder Low (LBA 15-8) Register (Address-1F4[174])

This register contains the low order 8 bits of the starting cylinder address or bits 15-8 of the Logical

Block Address.

4.2.7. Cylinder High (LBA 23-16) Register (Address-1F5[175])

This register contains the high order bits of the starting cylinder address or bits 23-16 of the Logical

Block Address.

4.2.8. Drive/Head (LBA 27-24) Register (Address 1F6[176])

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:

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 0 is selected When DRV=1, drive 1 is selected.

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.