Fujitsu MAA3182, MAC3045, MAB3045, MAB3091, MAC3091 manual

Models: MAC3091 MAB3045 MAA3182 MAC3045 MAB3091

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(1)User space

The user space is a storage area for user data. The data format on the user space (the length of data block and the number of data blocks) can be specified with the MODE SELECT or MODE SELECT EXTENDED command.

The default number of cylinders in the user space is 9,041 for MAA31xxxx, 8,491 for MAB30xxxx and 8,691 for MAC30xxxx. The user, however, can select the number of cylinders to be allocated in the user space by specifying 9,041 for MAA31xxxx, 8,491 for MAB30xxxx and 8,691 for MAC30xxxx as the maximum and the number of alternate cylinders + 1 as the minimum. The user can also specify the number of logical data blocks to be placed in the user space with the MODE SELECT or MODE SELECT EXTENDED command. When the number of logical data blocks is specified, as many cylinders as required to place the specified data blocks are allocated in the user space.

A number starting with 0 is assigned to each cylinder required in the user space in ascending order. If the number does not reach 9,041 (MAA31xxxx), 8,491 (MAB30xxxx) and 8,691 (MAC30xxxx), the rest of the cylinders will not be used.

Always one alternate cylinders can be established in the user space. Alternate cylinders will be used for alternate blocks when primary cylinders in the user space are used up. See Subsections 3.1.2 and 3.3.2 for details.

(2)Internal test space

The Internal test space is an area for diagnostic purposes only and its data block length is always 512KByte. The Internal test space consists of only 1 cylinder and outer-host cylinder is always assigned. The user cannot change the number of cylinders in the Internal test space or their positions.

The IDD reads or writes the data block in the Internal test space during the self-diagnostic test specified with a SEND DIAGNOSTIC command.

(3)System space

The system space is an area for exclusive use of the IDD itself and the following information are recorded. The length of the data block is always 512 bytes.

Defect list (P list and G list)

MODE SELECT parameter (saved value)

Statistical information (log data)

Controller control information

The above information are duplicated in several different locations for safety.

Note:

The system space is also called SA space.

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C141-E035-03EN

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Fujitsu MAA3182, MAC3045, MAB3045, MAB3091, MAC3091 manual