AT&T 6300 Service Manual page 55

SYSTEM OVERVIEW
The WD Controller is not supported by ROM BIOS 1.21 and earlier
versions. Both the DTC and the WD Controller are supported by
ROM BIOS 1.43 and later versions.
MOUNTING
BRACKET
DIP SWITCHES
(NOTE)
ESC] c=J2c=Ji_-
....----~-----.
~ C]~~c=JI
__
DCJ C]~~CJ I
CJ
c=J c=J
~ ~
c=J
====~
CJI I
CJCJCJC]I_-­
CJ
CJ CJC=I CJ CJ CJ
NOTE: DIP SWITCHES ARE MOUNTED LOWER ON
SOME REVISIONS OF THE HDU CONTROLLER
Figure 2-15. DTC Hard Disk Unit Controller
The J1, J2, and J3 connectors on the DTC Controller provide the
following:
• The J1 connector is the control connector. This connector
transfers the control signals to and from the HDUs. Two HDVs
can be installed using a Daisy Chain Connection.
• The J2 and J3 connectors are data connectors. These connectors
transfer data to and from the HDUs. The drive selection is
determined by the settings on the HDU, not by the choice of
connectors.
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