Toshiba MK4006GAH - Manual (Page 73)

Toshiba Corporation Digital Media Network Company
Page 73 of 153
© 2003, Copyright TOSHIBA Corporation All Rights Reserved
11.8.23 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 the DMA channel before issuing command.
- Data transfer is initiated by DMARQ and handled by the 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.
11.8.24 Read DMA EXT (25h)
COMMAND CODE 0 0 1 0 0 1 0 1 REGISTER
REGISTER SETTING NORMAL COMPLETION
DR drive no. no change
LBA
Low
Current
Previous
LBA(7:0)
LBA(31:24)
HOB=0
HOB=1 last address
last address
LBA
Mid
Current
Previous
LBA(15:8)
LBA(39:32)
HOB=0
HOB=1 last address
last address
LBA
High Current
Previous
LBA(23:16)
LBA(47:40) HOB=0
HOB=1 last address
last address
SC Current
Previous
sector count(7:0)
sector count(15:8)
HOB=0
HOB=1 00H
00H
FT Current
Previous
reserved
reserved HOB=0
HOB=1 no change
no change
This command is basically identical to Read DMA command except register setting.
This command is available in LBA addressing only.