U4 Family Product Manual, Rev. D

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2.2.2 Cable-select option

Computers that use cable-select determine the master and slave drives by selecting or deselecting pin 28, CSEL, on the interface bus. Master and slave drives are determined by their physical position on the cable. To enable cable select, set a jumper on pins 5 and 6 as shown in Figure 2 on page 18. Consult your computer manual to determine whether your computer supports this option.

2.3 Ultra ATA/66 cable

An 80-conductor 40-pin cable is required to run Ultra DMA mode 3 and

4.This cable uses even-numbered conductors connected to the ground pins to improve signal integrity.

Note. The drive supports both host and drive cable detection. The host detects the 80-conductor cable by sampling pin 34, CBLID–, on the interface bus. The drive detects the 80-conductor cable by sensing a capacitor at the host side through the CBLID– signal. The result is reported in a Fast Rise Detected bit (bit 13 of word 93 in the Identify drive parameter block).

2.4 Drive mounting

You can mount the drive in any orientation using four screws in the side- mounting holes or four screws in the bottom-mounting holes. See Figure 4 for drive mounting dimensions.

Important mounting precautions:

Allow a minimum clearance of 0.030 inches (0.76 mm) around the entire perimeter of the drive for cooling.

Use only 6-32 UNC mounting screws.

The screws should be inserted no more than 0.200 inch (5.58 mm) into the bottom mounting holes and no more than 0.14 inch (5.0 mm) into the side mounting holes.

Do not overtighten the mounting screws (maximum torque: 6 inch-lb).

Do not use a drive interface cable that is more than 18 inches long.

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Seagate ST34311A, ST32112A manual Cable-select option, Ultra ATA/66 cable, Drive mounting, Important mounting precautions