4.1 Mode Parameters

Note:

If transfer of this page descriptor is required by the MODE SENSE or MODE SENSE EXTENDED command, the IDD reports X '0E' as the page length (byte 1). However, if either X '0E' or X '0A' is specified for the page length in the MODE SELECT command, the IDD regards it as if the correct page length was specified. The X '0A' page length, is provided in consideration of compatibility with previous models, but it is recommended that the page length X '0E' be used by the INIT to support expansions in the specifications in the future.

See Section 2.1, "Data Buffer" concerning specification methods for the "Buffer Full Ratio" and "Buffer Empty Ratio" parameters in this page descriptor and details of data buffer operation.

a.Buffer full ratio

This parameter specifies the timing for the IDD to start reconnection processing in order to transfer data to the INIT by the READ or READ EXTENDED command.

The value specified in this parameter (n) shows the amount of data read to the IDD's data buffer from the disk media as a proportion [n/256] of the total capacity of the data buffer until reconnection processing with the SCSI bus is started. (Note)

If it is possible to transfer the amount of data specified in this parameter to the INIT from the data buffer, reconnection processing is executed and transfer of data to the INIT begins.

The default value for this parameter is X’00’. The host can also specify X’00’ for this parameter. If X’00’is specified, the IDD assigns an appropriate value for this parameter that is determined by IDD.

b.Buffer empty ratio

This parameter specifies the timing for the IDD to start reconnection when it is requested by the INIT to transfer data in the WRITE, WRITE EXTENDED or WRITE AND VERIFY command.

The value specified in this parameter (n) indicates the size of the empty area in the IDD's data buffer as a proportion of the total data buffer capacity of the IDD [n/256]. (Note)

While the IDD is writing data to the disk media, it is using the data pre-fetched to the data buffer in order, and when the empty space in the data buffer reaches the amount specified in this parameter, it executes reconnection processing, requesting transfer of the succeeding data.

If the total number of bytes in the transferred data block count specified in the command is less than the capacity of the buffer segment, all the data are pre-fetched in a batch, so the specification in this parameter is not applied.

The default value for this parameter is X’00’. The host can also specify X’00’ for this parameter. If X’00’is specified, the IDD assigns an appropriate value for this parameter that is determined by IDD.

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Fujitsu MAS3735, MAP3367, MAP3147, MAP3735, MAS3367 specifications Mode Parameters

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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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.