Command Specifications

The "Addressing boundary" field in the buffer descriptor indicates the addressing boundary in the data buffer which can be specified in the WRITE BUFFER Command and the READ BUFFER Command as a "Power" when expressed as a "Power of 2." The IDDs report X'02' (=22), indicating that it is possible to specify the address in 4-byte units. Also, the "Buffer capacity" field indicates the byte length of the size of the data buffer which can be operated by the WRITE BUFFER and READ BUFFER commands.

Note: Exercise caution regarding the following points when using this command.

If the WRITE BUFFER command or READ BUFFER command is used under a multi-initiator or multitask environment, it is necessary to be careful of the contents of the data buffer being changed by another initiator or a command that issues another task during the interval between completion of WRITE BUFFER command execution and execution of the READ BUFFER command.

(5)Mode = 1, 0, 1, 0 : Echo buffer

In this mode the IDD transfers data to the INIT from the echo buffer. The echo buffer shall transfer the same data as when the WRITE BUFFER command with the mode field set to echo buffer was issued. The BUFFER ID and BUFFER OFFSET fields are ignored in this mode.

(6)Mode = 1, 0, 1, 1 : Echo buffer descriptor

In this mode, a maximum of four bytes of READ BUFFER descriptor information is returned. The device server shall return the descriptor information for the echo buffer. The "Buffer Offset" field is reserved in this mode. The allocation length should be set to four or greater. The device server shall transfer the lesser of the allocation length or four bytes of READ BUFFER descriptor. The READ BUFFER descriptor is defined as shown in Figure 3.27.

Bit

Byte

7

6

5

4

3

 

 

 

2

1

0

 

 

 

0

Reserved

EBOS

1

Reserved

2

Reserved

Echo Butffer Capacity (MSB)

3

Echo Buffer Capacity (LSB)

Figure 3.27 READ BUFFER command: Echo buffer descriptor

The IDD return one in EBOS field, and the IDD verifies that echo buffer data from each initiator is the same as that previously written by the same initiator.

The "Buffer Capacity" field returns the size of the echo buffer X'01FC' in bytes aligned to a four-byte boundary.

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Fujitsu MAS3735, MAP3367, MAP3147, MAP3735, MAS3367 specifications Ebos, Read Buffer command Echo buffer descriptor
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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.

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.
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