Fc-Al Physical Interface; Physical Characteristics; Figure 17. Physical Interface; Figure 18. Port Bypass Circuit Physical Interconnect - Seagate 15K.4 - Cheetah - Hard Drive Product Manual

9.5

FC-AL physical interface

Figure 17 shows the location of the J1 Fibre Channel single connection attachment (FC-SCA) and the J6 con-
nector. Figure 19 provides the dimensions of the FC-SCA connector. Figure 20 provides the dimensions of the
J6 connector.
Details of the physical, electrical, and logical characteristics are provided within this section. The operational
aspects of Seagate's Fibre Channel drives are provided in the Fibre Channel Interface Manual..
Figure 17. Physical interface
9.5.1

Physical characteristics

This section defines physical interface connector.
9.5.1.1 Physical description
FIbre Channel drives may be connected in a loop together or with other compatible FC-AL devices. A maxi-
mum of 127 devices may have addresses; however, one of the addresses is reserved for a fabric port switch
device. This means 126 addresses are available for FC-AL devices. More FC-AL compatible devices may
physically reside on the loop, but they will not be functional because they would not be able to obtain valid
addresses.
Port bypass circuits (PBCs) allow devices to be inserted into unpopulated locations or removed from the loop
with loop operation recovery after a brief interruption. These PBCs are located external to the FC-AL device.
Figure 18 shows the relationship between the PBC and FC-AL device.
From Previous
Drive
Port Bypass
Circuit N–1
Drive N–1
Figure 18. Port bypass circuit physical interconnect
64
J6
Port Bypass
Circuit
To Next
Drive
MUX
Select
Serial Serial
In Out
Drive N
Port Bypass
Circuit N+1
Drive N+1
Cheetah 15K.4 FC Product Manual, Rev. C