Mode block descriptor
The format of the Mode Parameter block descriptor is as follows:
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| Density | Code |
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| 1 | (MSB) |
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| Number of Blocks (0) |
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| 3 |
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| 4 |
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| Reserved (0) |
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| 5 | (MSB) |
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| Block Length [0 or 800h] |
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| 7 |
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Mode Parameter block descriptor fields:
Density Code This specifies the format of the media loaded in the drive. See “REPORT DENSITY SUPPORT 44h” on page 137 for details.
Block Length This indicates the size of fixed blocks for fixed mode Read and Write commands. It is also used in the decision process on whether to report an illegal length record on reads.
00h The default value when the drive is in normal tape drive mode. 800h The tape drive is in
Read-Write Error Recovery mode page
The
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| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
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| 0 | PS (0) | Rsvd (0) |
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| Page Code {01h} |
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| 1 |
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| Additional Page Length {0Ah} |
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| 2 | Reserved (0) | TB (0) | Res (0) | EER (1) | PER [0] | DTE (0) | DCR (0) | |
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| 3 |
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| Read Retry Count |
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| Reserved (0) |
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| 8 |
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| Write Retry Count |
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| Reserved (0) |
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TB | Transfer Block | |
| 0 | Always set to 0, meaning that an unrecoverable data block will not be |
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EER | Enable Early Recovery | |
| 1 | The drive should attempt error correction before performing retries. |
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76 Commands