Toshiba MK6017MAP manual Set Multiple Mode C6h, Read DMA C8h/C9h

360014937

10.8.17 Set Multiple Mode (C6h)

COMMAND CODE		1 1 0 0 0 1 1 0	REGISTER
	REGISTER SETTING		NORMAL COMPLETION
DR	drive no.		no change
CY			no change
HD			no change
SN			no change
SC	The number of sectors / block		no change
FT			no change

This command enables the drive to perform Read and Write Multiple operations and sets the block count for these commands.

The Sector Count Register is loaded with the number of sectors per block. The drive supports 1,2,4,8 or16 sectors per block.

Upon receipt of the command, the drive sets BSY=1 and checks the content of Sector Count Register.

If the Sector Count Register contains a valid value and the block count is supported, the value is loaded for all subsequent Read Multiple and Write Multiple commands. And these commands are enabled to be executed. If a block count is not supported , this command shall be terminated with the report of an Aborted Command error , and Read Multiple and Write Multiple commands are disabled.

If the Sector Count Register contains 0 when the command is issued, Read Multiple and Write Multiple commands are disabled.

In case of software reset, the result depends on the setting of Set Feature command. If FT=66h, the mode is not changed. If FT = CCh, the mode reverts to power on default (16 sectors).

10.8.18 Read DMA			(C8h/C9h)
	COMMAND CODE			1 1 0 0 1 0 0 X	REGISTER
		REGISTER SETTING			NORMAL COMPLETION
	DR		drive no.		no change
	CY		starting cylinder		last possible
	HD		starting head		last possible
	SN		starting sector		last possible
	SC		no. of sector to read		00H
	FT				no change
	LBA		staring address		last address

This command is basically identical to Sector command except following features.

•Host initialize slave-DMA channel before issuing command.

-Data transfer is initiated by DMARQ and handled by slave-DMA channel in the host.

-Drive issues only one interrupt at the completion of each command to show the status is valid after data transfer.

During DMA transfer phase, either BSY or DRQ is set to 1.

When a command is completed, CY, HD, SN register (LBA register) shows the sector transferred the latest.

If the drive detects unrecoverable error, the drive terminate the command and CY, HD, SN register (LBA register) shows the sector where error occurred.

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