6. Serial ATA Questions & Answers
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LaCie d2 SATA II 3Gbits
User’s Manual
6. Serial ATA 3Gbits Questions and Answers
What is Serial ATA 3Gbits?
The Serial Advanced Technology Attachment (ATA) II marks the latest rung on the evolutionary ladder of SATA technology.
SATA II can deliver data at 300MB/s, twice as fast as its SATA predecessor and more than twice as fast as the Parallel ATA/
IDE (Integrated Drive Electronics) interface, which has long been used to connect peripheral devices to the computer. Initial
Serial ATA 3Gbits technology removed the performance bottleneck of the Parallel ATA specification, and follows a clearly
defined road-map to greater and greater data transfer rates and feature improvements.
Deriving its name from the way that it transmits signals, in a single stream, or serially, Serial ATA operates in a point-to-point
topology. This connectivity methodology delivers the entire available interface bandwidth to each device, allowing each device
to operate at its maximum throughput, and provides direct communication between the device and the system at any time,
reducing arbitration delays associated with shared bus topologies.
What are the features and benefits of Serial ATA 1.5 Gbits and Serial ATA 3Gbits? The Serial ATA specification provides
several key features that will help spur widespread implementation:
• Easy installation and configuration: There are no device IDs, termination or master/slave conflicts, and the standard
supports hot-plug connectivity. Drives can be added, upgraded or removed without having to power down the whole system.
• Improved reliability: Serial ATA also uses 32-bit cyclic redundancy checking (CRC) on all transfers to ensure correct data
transmissions. Due to this CRC capability, Serial ATA performs protection and recovery features at multiple levels: PHY layer,
link layer and transport and software layers.
• Simplified structure: Serial ATA utilizes a more efficient signaling voltage (250mV vs. 5V for Parallel ATA), and much
smaller, thinner and compact cables and connectors. Due to the simplified cabling (the reduction in the number of pins and
wires), the number of fault possibilities decreases.
• Seamless integration: Serial ATA maintains register and software compatibility with Parallel ATA, and should be transparent
to both the BIOS and operating system. Simply add more Serial ATA links to increase the number of connectivity points in
your system.