Interface

5.4.2 PIO data-in command protocol

Execution of the following commands involves data transfers from the device to the host system:

IDENTIFY DEVICE

READ SECTOR(S) (EXT)

READ MULTI (EXT)

READ BUFFER

SMART READ DATA

SMATR READ LOG SECTOR

READ LOG EXT

DEVICE CONFIGRATION IDENTIFY

Data of one or more sectors is transferred from the device to the host.

An outline of this protocol is as follows:

1)The device receives a PIO data-in command with the RegHD FIS.

2)If an error remaining in the device prevents command execution, the device sends the RegDH FIS with 1 set in the I bit.

3)When the device is ready to send data, it sets 0 in the BSY bit, 1 in the DRQ bit, and 1 in the I bit of the Status field of the PIO Setup FIS, then sends this FIS to the host. At this time, if the requested data is read from the last sector to be processed, the device sets 0 in both the BSY bit and DRQ bit of the E_Status field. Otherwise, the device sets 1 in the BSY bit and 0 in the DRQ bit of the E_Status field.

4)The device sends the DATA FIS to the host.

5)When all data has been transferred, command execution is completed. If any data remains to be transferred, this protocol is repeated starting from step 3). (The maximum data size is 8 KB.)

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Fujitsu MHW2080BS, MHW2100BS, MHW2120BS, MHW2040BS, MHW2060BS manual PIO data-in command protocol