IBM DJSA-210 - Travelstar 10 GB Hard Drive, Specifications

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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.
– Drive address Reg. 1 1 1 0 1
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 47. I/O address map
Travelstar 32GH/30GT/20GN hard disk drive specifications
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