IBM 7133 D40, Service Manual

Page: 66 / 306

Simplest Configuration
A 7133 that is in base configuration includes four disk drive modules. These modules
are installed in slots 1 through 4 at the front of the 7133. The other 12 disk drive slots
contain dummy disk drive modules. The disk drive modules are linked in groups of four.
Each group of four modules is linked to two external SSA connectors.
In the simplest configuration, the SSA loop is completed by connecting these two SSA
connectors to one of the two pairs of connectors on an SSA attachment in the using
system (see Figure 27).
No improvement in performance is gained if the disk drive modules are moved to other
slots and connected in more than one loop.
The cables are described in “SSA Cables for 7133 Models D40 and T40” on page 56.
The internal connections of the 7133 are shown in “Internal Connections (Model D40)”
on page 28 and “Internal Connections (Model T40)” on page 30.
For information about the rules for SSA loops, see the “Rules for SSA Loops” on
page 47.
2 2
1
7133 unit
4
5
8
9
1
16
12
13
4 3 2 1
Using system
A1 A2 B1 B2
Figure 27. Simplest Configuration
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7133 Models D40 and T40 Service Guide