Chapter 5ATAPI Interface
Read command
Bit | 7 | 6 | 5 | 4 |
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0 |
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| Operation code (08h) |
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1 |
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| Reserved |
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2 | (MSB) |
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3 |
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| Transfer Length |
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4 |
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5 |
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The Transfer Length specifies the number of fixed 512 byte blocks to be transferred. A transfer length of 0 indicates that no data is to be transferred but will initiate a
The DSC bit is reset (0) after this command is accepted and is set (1) when at least 52 blocks in the buffer are available for the next READ command. Issuing a READ command when the DSC bit is reset (0) will keep the ATA bus busy (BSY = 1) while the drive is reading the required data into the buffer. This delay could be more than a minute if exhaustive retries are required to read the data.
Page 52 | STT8000A Product Manual |
