Interface
5.3 Host Commands
The host system issues a command to the device by writing necessary parameters in related fileds in the shadow block registers and writing a command code in the Command field of the shadow block registers.
The device can accept the command when the BSY bit is 0 (the device is not in the busy status).
The host system can halt the uncompleted command execution only at execution of hardware or software reset.
When the BSY bit is 1 or the DRQ bit is 1 (the device is requesting the PIO data transfer) and the host system writes to the command field of the shadow block register, the correct device operation is not guaranteed.
5.3.1 Command code and parameters
Table 5.5 lists the supported commands, command code and the related fields to be written necessary parameters at command execution.
Table 5.5 Command code and parameters (1/3)
COMMAND NAME |
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| PARAMETER USED | |||||||||
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7 | 6 |
| 5 | 4 | 3 | 2 | 1 | 0 | FR | SC | SN | CY | DH | |
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RECALIBRATE | 0 | 0 |
| 0 | 1 | X | X | X | X | N | N | N | N | D |
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READ SECTOR(S) | 0 | 0 |
| 1 | 0 | 0 | 0 | 0 | R | N | Y | Y | Y | Y |
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READ LONG | 0 | 0 |
| 1 | 0 | 0 | 0 | 1 | R | N | Y | Y | Y | Y |
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WRITE SECTOR(S) | 0 | 0 |
| 1 | 1 | 0 | 0 | 0 | R | N | Y | Y | Y | Y |
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WRITE LONG | 0 | 0 |
| 1 | 1 | 0 | 0 | 1 | R | N | Y | Y | Y | Y |
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WRITE VERIFY | 0 | 0 |
| 1 | 1 | 1 | 1 | 0 | 0 | N | Y | Y | Y | Y |
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READ VERIFY SECTOR(S) | 0 | 1 |
| 0 | 0 | 0 | 0 | 0 | R | N | Y | Y | Y | Y |
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SEEK | 0 | 1 |
| 1 | 1 | X | X | X | X | N | N | Y | Y | Y |
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EXECUTE DEVICE DIAGNOSTIC | 1 | 0 |
| 0 | 1 | 0 | 0 | 0 | 0 | N | N | N | N | N |
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INITIALIZE DEVICE PARAMETERS | 1 | 0 |
| 0 | 1 | 0 | 0 | 0 | 1 | N | Y | N | N | Y |
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DOWNLOAD MICROCODE | 1 | 0 |
| 0 | 1 | 0 | 0 | 1 | 0 | Y | Y | Y | N | D |
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STANDBY IMMEDIATE | 1 | 0 |
| 0 | 1 | 0 | 1 | 0 | 0 | N | N | N | N | D |
1 | 1 |
| 1 | 0 | 0 | 0 | 0 | 0 | ||||||
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IDLE IMMEDIATE | 1 | 0 |
| 0 | 1 | 0 | 1 | 0 | 1 | Y | N | Y | Y | D |
1 | 1 |
| 1 | 0 | 0 | 0 | 0 | 1 | ||||||
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STANDBY | 1 | 0 |
| 0 | 1 | 0 | 1 | 1 | 0 | N | Y | N | N | D |
1 | 1 |
| 1 | 0 | 0 | 0 | 1 | 0 | ||||||
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