Interface
(28) IDENTIFY DEVICE (X’EC’)
The host system issues the IDENTIFY DEVICE command to read parameter information from the device. Upon receipt of this command, the drive sets the BSY bit to one, prepares to transfer the 256 words of device identification data to the host, sets the DRQ bit to one, clears the BSY bit to zero, and generates an interrupt. After that, the host system reads the information out of the sector buffer. Table 5.22 shows the values of the parameter words and the meaning in the buffer.
At command issuance (I/O registers setting contents)
1F7H(CM) | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 0 |
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1F6H(DH) | x | x | x | DV | xx |
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1F5H(CH) | xx |
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1F4H(CL) | xx |
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1F3H(SN) | xx |
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1F2H(SC) | xx |
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1F1H(FR) | xx |
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At command completion (I/O registers contents to be read)
1F7H(ST) | Status information |
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1F6H(DH) | x | x | x | DV | xx |
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1F5H(CH) | xx |
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1F4H(CL) | xx |
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1F3H(SN) | xx |
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1F2H(SC) | xx |
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1F1H(ER) | Error information |
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