I/O Implementation; System Control; Storage; Fibre Channel - Compaq DS20E - AlphaStation - 1 GB RAM Technical Manual

I/O Implementation

Two separate 64-bit PCI buses are provided, each with three
slots. As can be seen in the block diagram, the C-chip controls
both PCI control chips.
PCI 0 offers the following:
Slots for three PCI devices or two PCI devices and one
ISA device
Integrated control for system functions and bulkhead ports
Integrated control for two IDE ports
PCI 1 offers three PCI slots.
Flash ROM
(NVRAM functions)

Storage

The AlphaServer DS20E system offers up to nine internal
storage devices including a CD-ROM drive, floppy diskette
drive, one additional 5.25-inch removable media device, and
six hot-swap disk drives. The system supports up to 218.4
Gbytes of internal storage (using 36.4 GB disks). The disk
cage supports up to six Ultra3 SCSI Universal 1-inch disk
drives (9.1, 18.2, or 36.4 GB). The drives are available at
10,000 or 15,000 RPM.

Fibre Channel

Available on these AlphaServer systems is the next storage
interface, Fibre Channel, which eliminates issues with today's
SCSI interfaces such as distance, bandwidth, scalability, and
reliability. Fibre Channel (FC) is the answer to not only
server-to-storage connections but also to server-to-server
networking, because multiple protocols are supported. SCSI,
TCP/IP, video, or raw data can all take advantage of high-
performance, reliable Fibre Channel technology.
6
P-chip 0
C-chip
Interrupts
Config
P-chip 1
Block Diagram of I/O Control
At the rear of the system are connectors offering access to two
serial communications ports, one parallel port, and ports for
the keyboard and mouse. Six breakouts are also on the back
panel.

System Control

The system features module provides for the following:
Remote server management
Environmental monitoring
Power system event data collection
The module is located at the top rear of the system.
PCI Bus 0
Cypress
Chip
ISA
Super
Keyboard
I/O
Mouse
IDE
Adaptec
Tape
Chip
PCI Slot
PCI Slot
PCI Bus 1
With the KGPSA PCI Fibre Channel adapter, the DS20E
systems provide a storage interconnect that is 2.5 times as fast
as UltraSCSI: 100 vs 40 Mbytes/sec data throughput. The
KGPSA adapter allows you to manage storage including the
HSG80 RAID controller in a switched FC topology.

RAID (Redundant Array of Independent Disks)

The system can be configured with optional PCI RAID
controllers to organize disk data cost-effectively, improve
performance, and provide high levels of storage integrity.
The optional RAID controllers have the following features:
Support for hot-swap drives
Automatic rebuild after hot swap
Console support for booting system from RAID
RAID levels 0, 1, 0+1, 5
Optional write cache
Optional read cache
Support for command queuing
ISA Slot
Com1
Com2
Printer
Floppy
PK-0319D