Fujitsu MPF3XXXAT manual Bsy, Drdy DRQ Intrq, Ior, IOCS16

	Command
Parameter write
~	b c
a

BSY

Status readStatus read

e • • • • e

DRDY

DRQ

d	f	d
		• • • •

INTRQ

Data transfer

Expanded

Command

Min. 30 μs (*1)

• • •

DRQ

INTRQ

Data Reg.

Selection

Data

IOR-

Word 0 1

IOCS16-

• • • •

• • • •

• • • •

2255

*1 When the IDD receives a command that hits the cache data during read-ahead, and transfers data from the buffer without reading from the disk medium.

Figure 5.2 Read Sector(s) command protocol

Even if the error status exists, the drive makes a preparation (setting the DRQ bit) of data transfer. It is up to the host whether data is transferred. In other words, the host should receive the data of the sector (512 bytes of uninsured dummy data) or release the DRQ by resetting.

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