MD1050-DCC M-Systems Inc., MD1050-DCC Datasheet - Page 16

• Manufacturer Part Number: MD1050-DCC
• Description: Diskonchip Ide Pro Data Sheet
• Manufacturer: M-Systems Inc.

4.8
This register selects the device and defines address translation mode as CHS or LBA. In CHS mode
it provides the head address. In LBA mode, it provides the assignment for LBA[27:24]. This
register is write-only when BSY=0 and DRQ=0.
4.9
The Sector Count register contains the number of data sectors requested to be transferred during a
read or write operation between the host and the device. A zero value specifies 256 sectors. The
command is successful if this register is zero on command completion. This register is write-only
when BSY=0 and DRQ=0.
15
Bit No.
Bit 7
0-3
0-3
4-7
Bit 7
4
6
1
Device/Head Register (Read/Write)
Sector Count Register (Read/Write)
HS[0:3] (Head Starting Address Bits 0-3). When LBA=0 (CHS), these bits contain the head
address of the starting CHS address. Bit HS3 is the most significant bit.
DEV (Device Address).
0 = Master drive selected.
1 = Slave drive selected.
LBA (Address Mode Select).
0 = CHS (Cylinder, Head, Sector) mode.
1 = LBA (Logical Block Address) mode.
LBA[24:27] (Logical Block Addresses 24-27). When LBA=1 (LBA mode), these bits represent
LBA bits 24-27.
Reserved.
Bit 6
LBA
Bit 6
Reserved
Bit 5
Bit 5
1
DiskOnChip IDE Pro Data Sheet, Rev. 1.5
Bit 4
DEV
Bit 4
Sector Count
CHS Mode
CHS Mode
LBA Mode
LBA Mode
Description
LBA27
Bit 3
HS3
Bit 3
LBA26
Bit 2
HS2
Bit 2
LBA25
Bit 1
Bit 1
HS1
91-SR-012-01-8L
LBA24
Bit 0
Bit 0
HS0