IBM IC25N005ATDA04, Технические характеристики

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7.12 Addressing of HDD registers
The host addresses the drive through a set of registers called a Task File. These registers are mapped
into the host's I/O space. Two chip select lines (CS0- and CS1-) and three address lines (DA00–02) are
used to select one of these registers, while a DIOR- or DIOW- is provided at the specified time.
The chip select line CS0- is used to address the Command Block registers while the CS1- is used to
address Control Block registers.
The following table shows the I/ O address map.
Device control Reg. Alt. Status Reg. 0 1 1 0 1
Control Block Registers
Command Reg. Status Reg. 1 1 1 1 0
Drive/Head Reg. Drive/Head Reg. 0 1 1 1 0
Cylinder high Reg. Cylinder high Reg. 1 0 1 1 0
Cylinder low Reg. Cylinder low Reg. 0 0 1 1 0
Sector number Reg. Sector number Reg. 1 1 0 1 0
Sector count Reg. Sector count Reg. 0 1 0 1 0
Features Reg. Error Reg. 1 0 0 1 0
Data Reg. Data Reg. 0 0 0 1 0
Command Block Registers
DIOW- = 0 (Write) DIOR- = 0 (Read) DA00 DA01 DA02 CS1- CS0-
Figure 52. I/O address map
Travelstar 48GH, 30GN & 15GN hard disk drive specifications
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