Interface
•SET MAX ADDRESS
A successful READ NATIVE MAX ADDRESS command shall immediately precede a SET MAX ADDRESS command.
This command allows the maximum address accessible by the user to be set in LBA or CHS mode. Upon receipt of the command, the device sets the BSY bit and saves the maximum address specified in the DH, CH, CL and SN registers. Then, it clears BSY and generates an interrupt.
The new address information set by this command is reflected in Words 1, 54, 57, 58, 60 and 61 of IDENTIFY DEVICE information. If an attempt is made to perform a read or write operation for an address beyond the new address space, an ID Not Found error will result.
When SC register bit 0, VV (Value Volatile), is 1, the value set by this command is held even after power on and the occurrence of a hard reset. When the VV bit is 0, the value set by this command becomes invalid when the power is turned on or a hard reset occurs, and the maximum address returns to the value (default value if not set) most lately set when VV bit = 1.
After power on and the occurrence of a hard reset, the host can issue this command only once when VV bit = 1. If this command with VV bit = 1 is issued twice or more, any command following the first time will result in an Aborted Command error.
At command issuance (I/O registers setting contents)
1F7H(CM) | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 |
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1F6H(DH) | x | L | x | DV | Max head/LBA [MSB] | |||
1F5H(CH) | Max. cylinder [MSB]/Max. LBA |
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1F4H(CL) | Max. cylinder [LSB]/Max. LBA |
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1F3H(SN) | Max. sector/Max. LBA [LSB] |
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1F2H(SC) | xx |
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| VV |
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1F1H(FR) | xx |
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