3.1 Data Space

Cylinder skew

Head

Cylinder skew

P

Track skew

Head

P+1

Leading logical sector in head p+1

Figure 3.5 Track skew/head skew

The number of physical sectors (track skew factor and head skew factor) corresponding to the skew time varies depending on the logical data block length because the track skew and the head skew are managed for individual sectors. The IDD automatically determines appropriate values for the track skew factor and the head skew factor according to the specified logical data block length. The value can be read out by the MODE SENSE or MODE SENSE EXTENDED command after the track has been formatted.

3.1.4Sector format

Each sector on the track consists of an ID field, a data field, and a gap field which separates them. Figure 3.6 gives sector format examples.

SCT

PLO

 

 

 

 

 

 

 

 

 

 

 

 

SCT

 

 

 

 

SM1

DATA1

SM2

DATA2

BCRC

 

ECC

PAD

 

 

 

 

 

 

 

 

 

 

 

G1

Sync

 

 

G2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SCT

PLO

 

 

 

 

 

 

 

 

Servo

 

 

 

 

 

 

 

SCT

 

SM1

DATA1

SM2

DATA3

PAD

 

 

 

 

 

 

 

PLO

SM1

DATA1

SM2

DATA4

BCRC

ECC

PAD G3

G1

Sync

 

G2

 

 

G1 Sync

 

 

 

Figure 3.6 Sector format

C141-E163

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Fujitsu MAP3735FC, MAP3147FC manual Track skew/head skew, Sector format

MAP3735FC, MAP3147FC specifications

Fujitsu has been a prominent player in the hard disk drive market, with its MAP3147FC and MAP3735FC models standing out in terms of performance and reliability. These drives are engineered to meet the growing demands of enterprise applications, providing robust solutions for data storage in critical environments.

The Fujitsu MAP3147FC, with a capacity of 147 GB, is optimized for high-speed data access and storage efficiency. This 3.5-inch SCSI drive operates at a rotational speed of 15,000 RPM, ensuring rapid data retrieval and minimized latency, making it ideal for applications requiring quick transaction processing. It features a 4 Gbps Fibre Channel interface, which enhances connectivity and system integration, promoting seamless communication between devices in storage area networks.

On the other hand, the MAP3735FC model offers a higher capacity of 300 GB. It shares similar specifications with its counterpart, including the 15,000 RPM speed, which guarantees top-notch performance for mission-critical applications. The MAP3735FC, like the MAP3147FC, incorporates advanced technologies such as Command Queuing, which optimizes the execution of multiple read and write commands in a queue. This feature is particularly beneficial in environments with high I/O demands, improving overall system throughput and efficiency.

Both drives utilize sophisticated error correction techniques, ensuring data integrity and reliability. They are equipped with features like S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology), which continuously monitors the health of the drives and helps predict potential failures, allowing for proactive maintenance and data protection.

In terms of physical characteristics, both models are designed to withstand the rigors of continuous operation. They are built with a rugged casing to protect against vibration and shock, making them suitable for use in enterprise-level servers and storage systems. Their design also allows for efficient heat dissipation, which is critical for maintaining optimal performance during extended use.

In summary, Fujitsu's MAP3147FC and MAP3735FC hard drives embody a combination of high speed, reliability, and advanced features tailored for enterprise environments. Their robust performance, large storage capacities, and reliable error correction technologies make them an excellent choice for businesses looking to optimize their data storage solutions and ensure seamless operation in demanding applications. With Fujitsu's commitment to quality and innovation, these models continue to meet the evolving needs of the data storage industry.