Cable Select is an alternate method to using the Master/Slave jumpers for identifying the Master or Slave device on ATA/ATAPI systems. Cable Select can save time during the assembly process for large volume system integrators and is quickly becoming the industry default setting for new drive shipments. All Seagate ATA drives can be configured for either Cable Select or Master/Slave with jumper settings, but not both simultaneously. Additionally, if there are two devices on an ATA channel/cable, both devices must use either Cable Select or Master/Slave settings.

Both Cable Select and Master/Slave settings are made using jumpers on the options jumper block of the device (typical Seagate ATA drive shown). Cable Select settings (pins 5-6) require specific placement of the master and slave device on the cable according to which type of cable is used. Alternately, devices using Master/Slave settings (pins 7-8) can be placed in either the middle or end cable connector of the cable.

Cable Select. The drive is configured at the factory for a cable select setting. This allows the drive to assume the proper role of master or slave based on the connector used on the cable. For the cable select setting to work properly, the cables you are using must support the cable select feature. Current UltraATA cables with the 3 colored connectors do support this feature.

Master or single drive. If you are installing your Seagate hard drive as the only drive in the system or if it will be the primary boot drive for the system, the jumper should be set on pins 7 and 8.

Drive as slave. If you are installing the drive as an additional drive in your system, the drive should be set as slave by removing all jumpers. Remember to confirm that the original drive is set to a master position (If the limit capacity jumper is required for your installation it will need to remain in place).

Drive as master with a non-ATA-compatible slave. Set a jumper on pins 5 and 6 and a jumper on pins 7 and 8. Use this jumper setting only if the drive does not work as a master.

Limit drive capacity. Use this when either you start up your computer and see the message, "Hard disc drive controller failure", your computer does not recognize your newly installed hard drive, or your system stops responding during the boot process after installing this new drive.

This occurs in some computers that do not support high-capacity drives. To address this problem, install the capacity-limiting jumper on your new hard drive, as shown in the figure above (this will not affect the storage capacity of your drive).

The standard 40-pin ATA ribbon cable and the 40-pin/80-conductor cable give different drive behavior when using Cable Select. If using the 40-pin/80-conductor cable, attach the blue end connector to the system board or host controller, the grey middle connector to the Slave, and the black end connector to the Master.

With the release of the U6 and Barracuda ATA IV drives (June, 2001), a single ATA drive configured using Cable Select will show as Master in either the middle or the end connector of the 40-pin cable. This holds for only single drive applications and only for the standard 40-pin cable. If your drive does not give the desired Master/Slave indication using Cable Select, it is recommended to use the Master/Slave settings.