Seagate ST91000642NS User Manual

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Constellation.2 Serial ATA Product Manual, Rev. B
4.2
Configuring the drive
Each drive on the Serial ATA interface connects point-to-point with the Serial ATA host adapter. There is no 
master/slave relationship because each drive is considered a master in a point-to-point relationship. If two 
drives are attached on one Serial ATA host adapter, the host operating system views the two devices as if they 
were both “masters” on two separate ports. Both drives behave as if they are Device 0 (master) devices.
Serial ATA drives are designed for easy installation. It is usually not necessary to set any jumpers on the drive 
for proper operation; however, if you connect the drive and receive a “drive not detected” error, your SATA-
equipped motherboard or host adapter may use a chipset that does not support SATA speed autonegotiation.
4.3
Serial ATA cables and connectors
The Serial ATA interface cable consists of four conductors in two differential pairs, plus three ground connec-
tions. The cable size may be 30 to 26 AWG with a maximum length of one meter (39.37in). See Table 5 for 
connector pin definitions. Either end of the SATA signal cable can be attached to the drive or host.
For direct backplane connection, the drive connectors are inserted directly into the host receptacle. The drive 
and the host receptacle incorporate features that enable the direct connection to be hot pluggable and blind 
mateable.
For installations which require cables, you can connect the drive as illustrated in Figure 5.
Figure 5. Attaching SATA cabling
Each cable is keyed to ensure correct orientation. Constellation.2 Serial ATA drives support latching SATA con-
nectors. 
Power cable
Signal cable
Signal connector
Power connector