CHAPTER 1 Command Processing

1.1Command Format

1.2Status Byte

1.3Outline of Command Processing

1.4Command Queuing Function

1.5UNIT ATTENTION Condition

1.6Sense Data Hold State

1.7Command Processing Exceptions

1.8Data Block Addressing

This chapter describes the basic logical specifications of the IDD command processing functions.

Note: The IDD operates as the target (TARG) on the SCSI bus. In the explanations in this chapter, the IDD is mentioned as “TARG”, except in cases where a particularly clear distinction is necessary.

1.1Command Format

Input/output operation commands from INIT (initiator) to the IDD are accomplished by the CDB (Command Descriptor Block). The CDB is information transferred from INIT to TARG in the COMMAND phase. In a number of commands, the parameters which are necessary for command execution in the DATA OUT phase may be specified in addition to the CDB specification. Details concerning these are described in the specifications for each individual command in Chapter 3.

The CDB used by the IDD has 3 formats, these formats have length of 6, 10 and 12 bytes. The basic format of each respective CDB is shown in Figures 1.1, 1.2 and 1.3.

Byte

Bit

7

6

5

 

4

3

 

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

 

 

 

Operation Code

 

 

 

 

 

 

 

 

 

 

 

 

 

1

 

LUN

 

 

 

Logical Block Address (MSB)

 

 

 

 

 

 

 

 

 

 

 

 

2

 

 

 

Logical Block Address

 

 

 

 

 

 

 

 

 

 

 

 

 

3

 

 

 

Logical Block Address (LSB)

 

 

 

 

 

 

 

 

 

 

 

 

 

4

 

 

 

Transfer Data Length

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5

 

 

 

Control Byte

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 1.1 6-Byte CDB Basic Format

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Fujitsu MAS3367, MAP3367, MAP3147, MAS3735, MAP3735 specifications Command Format, Lun
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MAP3735, MAP3147, MAS3367, MAP3367, MAS3735 specifications

Fujitsu, a renowned leader in technology and innovation, has developed a variety of reliable hard disk drives (HDDs) that cater to a wide range of data storage needs. Among these, the MAS3735, MAP3367, MAS3367, MAP3147, and MAP3735 series stand out for their advanced features and exceptional performance.

The MAS3735 is a high-capacity enterprise-class drive that boasts a storage capacity of up to 300 GB. Its 10,000 RPM spindle speed ensures rapid data retrieval and efficient performance, making it ideal for data-intensive applications. It utilizes a Serial Attach SCSI (SAS) interface, which allows for improved data transfer rates and increased reliability compared to traditional SATA drives. The drive is designed with advanced technologies such as error recovery and data integrity features, ensuring the safety and security of critical data.

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On the other hand, both MAP3147 and MAP3735 models provide versatile solutions for various applications, supporting capacities from 36 GB to 147 GB. The MAP3147, with its 10,000 RPM speed, is optimized for workloads requiring quick access and high throughput, making it suitable for transactional systems and enterprise applications. The MAP3735, while offering comparable capacity, emphasizes exceptional reliability and durability, which is crucial for environments that involve heavy data loads.

All these Fujitsu HDDs are characterized by their robust construction, reliability, and efficiency. They are built to withstand heavy workloads and are equipped with features like advanced thermal management and acoustic noise reduction, ensuring they operate effectively in data center environments.

In conclusion, Fujitsu's MAS3735, MAP3367, MAS3367, MAP3147, and MAP3735 series HDDs are designed for high performance and reliability, catering to both enterprise and mid-range environments. Their advanced features make them a strong choice for businesses looking to enhance their storage solutions while maintaining data integrity and system performance.
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