IBM DU3 2104, Hardware Technical Information

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SCSI Interface Cards
Attached to the back of the backplane in a fully configured 2104 Model DU3 or 2104
Model TU3 are two SCSI interface cards. Both cards can be used to connect host
machines to the 2104 disk enclosure. A SCSI interface card provides the following
functions:
v
Supports SCSI Enclosure Services at the SCSI node at address 15 on the external
SCSI bus
v
Reads the Vital Product Data (VPD) for the backplane, the fan-and-power-supply
assembly, the fan assembly, the switch card, the SCSI interface card, and the SCSI
bus bridge card
v
Inputs the fan-and-power-supply assembly fault lines
v
Controls the fan-and-power-supply assembly fault LEDs and the fan assembly fault
LED
v
Controls the fault LED at the front of the 2104 Model DU3 or 2104 Model TU3
v
Monitors the EPOW (Early Power-Off Warning) signal from the power supplies, and
passes this information to the disks when needed
v
Supports hot plugging of disk drive modules
v
Detects and indicates faults within itself
v
Supports LVD (low-voltage differential) Ultra3 SCSI (160MB per second data rate)
Note: Single-ended (SE) SCSI is not supported.
The other SCSI interface card detects and indicates only faults within itself. However, if
the first SCSI interface card fails, the second SCSI interface card provides all the
functions previously provided by the other SCSI interface card.
If the 2104 contains only one SCSI interface card, the SCSI interface card provides all
the functions listed above.
Chapter 1. Introduction
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