Command Processing

Furthermore, this field may be used with a different meaning, or it may not have any meaning at all, depending on the type of command. There are also some commands which allocate 3 or more bytes as the transfer data length field. Detailed specifications of these commands are described in the individual command specifications in Chapter 3.

 

a.

Transfer block count

 

 

 

 

 

 

 

 

 

 

 

When the “Transfer Data Length” is specified as the “Transfer Block Count,” this field specifies

 

 

the number of logical data blocks to be transferred between INIT and the IDD.

 

 

In commands where this field is 1 byte in length, if the field’s specified value is 0, it is regarded

 

 

as specifying 256 blocks, and it is possible to specify a block count ranging from 1 to 256 blocks.

 

 

On the other hand, in commands where this field is 2 bytes in length, if the field’s specified value

 

 

is 0, no data transfer is executed. It is possible to specify a block count ranging from 0 to 65,535

 

 

blocks.

 

 

 

 

 

 

 

 

 

 

 

 

 

b.

Transfer byte length or parameter list length

 

 

 

 

 

 

 

When this field is specified as the “Transfer Byte Length” or “Parameter List Length,” that

 

 

command specifies data length to be transferred between the INIT and the IDD, expressed as the

 

 

number of bytes. When 0 is specified in this field, data transfer is not executed, except in cases

 

 

where it is expressly stated in the individual command specifications in Chapter 3.

 

 

In commands which send parameters necessary for executing a command from the INIT to the

 

 

IDD, this field is called the “Parameter List Length,” and it specifies the total number of types in

 

 

the parameter list which the INIT is sending.

 

 

 

 

 

 

 

On the other hand, in commands for receiving information from the IDD (REQUEST SENSE,

 

 

INQUIRY, etc.), this field is called the “Transfer Byte Length,” and specifies the maximum

 

 

number of bytes which the INIT can

receive (the number of bytes of area secured within the

 

 

INIT for receiving information). The IDD transfers either the number of effective bytes of the

 

 

type of information specified in the command, or the value specified in the “Transfer Byte

 

 

Length” field, whichever is the smallest number of bytes, and only that number, to the INIT.

(5)

Control byte

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bit 7

 

6

 

5

4

 

3

2

 

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

0

 

0

0

 

0

0

 

0

Link

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

a.

Link

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Command link is specified by this bit is “1.” Details of the operation of the command link are

 

 

described in Section 1.3.2.

 

 

 

 

 

 

 

 

 

b.

Bit 7, 6

(vendor unique)

 

 

 

 

 

 

 

 

 

 

 

Except in cases where it is expressly specified in the individual commands, specification of these

 

 

bits has no meaning, and the IDD disregards the specified values.

 

 

 

1 - 4

C141-E167

Page 22
Image 22
Fujitsu MAS3735, MAP3367, MAP3147, MAP3735, MAS3367 specifications Command Processing

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.

Similarly, the MAP3367 and MAS3367 models are geared towards both enterprise and mid-range server environments, providing a storage capacity of up to 300 GB as well. These drives also operate at a spindle speed of 15,000 RPM, offering swift access times that enhance overall system performance. The MAP3367 employs the Ultra 320 SCSI interface, allowing for significant bandwidth and ensuring data is transmitted efficiently.

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.