Interface
(21) READ BUFFER (X’E4’)
The host system can read the current contents of the data buffer of the device by issuing this command. Upon receipt of this command, the device sets the BSY bit of Status register and sets up for a read operation. Then the device sets the DRQ bit of Status register, clears the BSY bit, and generates an interrupt. After that, the host system can read up to 512 bytes of data from the buffer.
At command issuance (I/O registers setting contents)
1F7H(CM) | 1 | 1 | 1 | 1 | 0 | 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) |
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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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