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390742-001
Service Reference Guide, dc7600
Serial and Parallel ATA Drive Guidelines and Features
4.8.1 Legacy Mode
The Legacy mode is used to access devices attached to an embedded ATA controller. Each
channel of the controller requires two fixed I/O address ranges and an IRQ.
■
Primary Channel
❏
Command block: 1F0h - 1F7h
❏
Control block: 3F6h
❏
IRQ: 14
■
Secondary Channel
❏
Command block: 170h - 177h
❏
Control block: 376h
❏
IRQ: 15
4.8.2 Native Mode
The native mode is used to access devices attached to additional ATA controllers and is not
supported by many legacy operating systems. Addresses are assigned by PCI Plug-n-Play BIOS
and the IRQ is shared with multiple controllers. Base Address Registers for the Command and
Control Block are found in the PCI Configuration Space.
■
Offset 10h—Primary Command base address
■
Offset 14h—Primary Control base address
■
Offset 18h—Secondary Command base address
■
Offset 1Ch—Secondary Control base address
Summary of Contents for Compaq Businessdc7600
Page 2: ......
Page 10: ...viii 390742 001 Service Reference Guide dc7600 Contents ...
Page 14: ...1 4 390742 001 Service Reference Guide dc7600 Installing the Operating System ...
Page 212: ...A 12 390742 001 Service Reference Guide dc7600 Connector Pin Assignments ...
Page 226: ...C 12 390742 001 Service Reference Guide dc7600 POST Error Messages ...
Page 254: ...D 28 390742 001 Service Reference Guide dc7600 Troubleshooting Without Diagnostics ...
Page 268: ...Index 8 390742 001 Service Reference Guide dx7600 Index ...