Fujitsu MPD3XXXAT manual Other commands, DMA data transfer commands

Models: MPD3XXXAT

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5.4.4Other commands

READ MULTIPLE

SLEEP

WRITE MULTIPLE

See the description of each command.

5.4.5DMA data transfer commands

READ DMA

WRITE DMA

Starting the DMA transfer command is the same as the READ SECTOR(S) or WRITE SECTOR(S) command except the point that the host initializes the DMA channel preceding the command issuance.

The interrupt processing for the DMA transfer differs the following point.

The interrupt processing for the DMA transfer differs the following point.

a)The host writes any parameters to the Features, Sector Count, Sector Number, Cylinder, and Device/Head register.

b)The host initializes the DMA channel

c)The host writes a command code in the Command register.

d)The device sets the BSY bit of the Status register.

e)The device asserts the DMARQ signal after completing the preparation of data transfer. The device asserts either the BSY bit during DMA data transfer.

f)When the command execution is completed, the device clears both BSY and DRQ bits and asserts the INTRQ signal.

g)The host reads the Status register.

h)The host resets the DMA channel.

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C141-E069-02EN

Page 139
Image 139
Fujitsu MPD3XXXAT manual Other commands, DMA data transfer commands