AMD hard drive cables free download

File name hard_drive_cables.pdf

AMD GeodeTM System Platforms 80-Conductor Hard Drive Cable Issues 1.0 Scope This document discusses known issues when using an 80- The 80-conductor cable only connects the two external conductor hard drive cable on an AMD GeodeTM system device PDIAG signals together and grounds the PDIAG on platform containing on-board CompactFlash connectors. the motherboard connector. When a hard drive is plugged into the external connector and a CompactFlash is plugged into the internal connector, the hard drive does not see the 2.0 Discussion PDIAG from the CompactFlash on the motherboard. How- ever, the CompactFlash on the motherboard does see Today, many hard drive cables supplied with platforms or PDIAG asserted since the cable connects this signal to hard drives are 80-conductor cables. These differ from the ground. previous standard 40-conductor cables in that every other conductor is a ground conductor that improves the signal Therefore, motherboards cannot support a CompactFlash quality by allowing for higher transfer rates across the plugged into an on-board connector while a hard drive is cable. attached via an 80-conductor cable. The two cables route the PDIAG signal differently. The 40- However, there are no issues when a CompactFlash is conductor cable routes PDIAG to all three connectors on plugged into an 80-conductor cable through an adapter. the cable assembly allowing the PDIAG to flow back and When a 40-conductor cable is used, the on-board forth between an on-board CompactFlash connector and CompactFlash connector may be used when an external the external hard drive. hard drive is connected. For details on 80-conductor and 40-conductor hard drive cables, see the ATA 6 Specification. Revision 1.0 - January 2002 - Confidential 1