Sense Data
The extension sense data format is used for the sense data created when an error occurs. This format is described below.
Bit | 7 | 6 | 5 | 4 |
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0 | Valid |
| Error class (7) |
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| Error code (0) |
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1 |
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| Segment data number (0) |
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2 | File mark | EOM | ILI | Reserved |
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3 |
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| Information byte (MSB) |
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4 |
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| Information byte |
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5 |
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| Information byte |
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6 |
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| Information byte (LSB) |
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7 |
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| Additional sense byte (0) |
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Following is a description of the individual bits and bytes.
Valid:
When set to 0, this bit indicates that the data in the data byte is invalid. When set to 1, the data is valid.
ILI:
This is the illegal length bit. When set to 1, this bit indicates that the transfer length or assigned length specified with a command is not the same as the actual data length required by the scanner.
Interface Specifications