User manual FREECOM AIT-SDX800

[. . . ] SDX-800V SDX-800V/R 5. 25"Model Product Specification Manual Version 1. 0 November 2005 Copyright © 2005, Sony Corporation. NOTE: This Product Specification Manual is applicable for AIT-3Ex drive. Notice This document contains proprietary information which is protected by copyright. No part of this document may be photocopied, reproduced or translated to another language without prior written consent of Sony. The information contained in this document is subject to change without notice. [. . . ] The Allocation Length must fall on header or block descriptor boundaries. If the Allocation Length does not fall on these boundaries then the drive returns CHECK CONDITION status with the ILLEGAL REQUEST sense key set, unless the value is greater than that required for the specified page. If the Page Code is ZERO, the Host requires MODE SENSE to only return the four-byte header the one eight-byte block descriptor, therefore the Allocation Length must be set to 0Ch. The value of the Page Control Field is then not checked by the drive and may be set to any value. If the Allocation length is non ZERO and less than 4, the drive will return CHECK CONDITION status, and ILLEGAL REQUEST sense key. The MODE SENSE data contains a four-byte header, followed by one eight-byte block descriptor, followed by ZERO or more variable length pages, depending on the Page Code and the Allocation Length. Table 6-53: MODE SENSE data Bit Byte 0 1 2 3 5 6 7 8 9 10 11 7 6 5 4 3 2 1 0 WP (MSB) Mode Data Length Medium Type (00h) Buffered Mode (001b) Block Descriptor Length (08h) Number of Blocks (00 00 00h) Speed (00h) (LSB) Reserved (MSB) Block Length (LSB) Mode Data Length: The mode data length specifies the length in bytes of the following mode sense data that is available to be transferred during the DATA IN phase. The mode data length does not include itself but does include the total length of all requested MODE SENSE pages. SONY AIT-3Ex drive SDX-800V series Ver. 1. 0 6-57 6. Command Specification Media Type: The media value will be ZERO as only one media type is supported. MODE SENSE WP: A Write Protected bit of ZERO indicates that the tape is write enabled. A Write Protected bit of one indicates that the tape is write protected. Buffered Mode: if this bit is set to ZERO, the drive will not report a GOOD status on WRITE commands until the data blocks are actually written on the tape. If set, the drive is in buffered mode and may report a GOOD status on WRITE commands as soon as the data block has been transferred to the drive's buffer. (Not support) If the Buffered Mode field is ONE, then drive reports GOOD status on WRITE commands as soon as the data block has been transferred to the buffer, this field should be set to ONE. Block Descriptor Length: returns a value of 8, which specifies the length in bytes of the following Block Descriptor. Density Code: The drive returns 30h, 31h, 32h, and 3Bh in the Density Code field. Number of Blocks: The Number of Blocks field is ZERO, indicating that an unspecified (or unknown) number of the remaining logical blocks on the tape may have the media characteristics specified by the Block Descriptor. Block Length: The Block Length field specifies the length in bytes of each logical block transferred over the SCSI bus. Any other value indicates the number of bytes per block that the drive must handshake over the bus. This establishes Block Length such that the Transfer Length for read, write command will be a block count not a byte count. If Block Length is 1, the drive will return the CHECK CONDITION status with an ILLEGAL REQUEST sense key. Note: It is value of this field together with the Fixed Bit Field in the READ, or WRITE commands that determine whether the drive is in Fixed or Variable block mode. Page Descriptor: The supported pages are fully documented in the MODE SELECT clause of this Chapter. PS: When the Page Savable bit is set, this indicates that the page contains saved parameters. [. . . ] The host has limited access, and cannot perform any commands which would cause tape motion. The host can, however, load a tape, if one is inserted, and can execute any diagnostic tests which do not require tape motion. The host has access to all command operations, including those which access the tape, set configurations and run diagnostic tests. Over Length: The incorrect length condition that exists after executing a read command when the length of the actual block read exceeds the requested transfer length in the command descriptor block. [. . . ]