SST55LD019C-45-I-MVWE View Datasheet(PDF) - Silicon Storage Technology
Part Name
Description
Manufacturer
SST55LD019C-45-I-MVWE Datasheet PDF : 79 Pages
| |||
Data Sheet
11.2.1.12 Read-DMA - C8H
ATA Flash Disk Controller
SST55LD019A / SST55LD019B / SST55LD019C
Bit ->
7
6
5
4
3
2
1
0
Command (7)
C8H
C/D/H (6)
1
LBA
1
Drive
Head (LBA 27-24)
Cyl High (5)
Cylinder High (LBA 23-16)
Cyl Low (4)
Cylinder Low (LBA 15-8)
Sec Num (3)
Sector Number (LBA 7-0)
Sec Cnt (2)
Sector Count
Feature (1)
X
This command executes in a similar manner to the Read-Sector(s) command except for the following:
- the host initializes the DMA channel prior to issuing the command;
- data transfers are qualified by DMARQ and are performed by the DMA channel;
- the ATA Flash Disk Controller issues only one interrupt per command to indicate that data transfer has
terminated and status is available.
During the DMA transfer phase of a Read-DMA command, the ATA Flash Disk Controller will provide
the status of the BSY bit or the DRQ bit until the command is completed.
11.2.1.13 Read-Multiple - C4H
Bit ->
7
6
5
4
3
2
1
0
Command (7)
C4H
C/D/H (6)
1
LBA
1
Drive
Head (LBA 27-24)
Cyl High (5)
Cylinder High (LBA 23-16)
Cyl Low (4)
Cylinder Low (LBA 15-8)
Sec Num (3)
Sector Number (LBA 7-0)
Sec Cnt (2)
Sector Count
Feature (1)
X
Note: The current revision of the ATA Flash Disk Controller can support up to a block count of 1 as indicated in the Identify-Drive Com-
mand information.
The Read-Multiple command is similar to the Read-Sector(s) command. Interrupts are not generated
on every sector, but on the transfer of a block which contains the number of sectors defined by a Set
Multiple command.
Command execution is identical to the Read-Sectors operation except that the number of sectors
defined by a Set Multiple command are transferred without intervening interrupts. DRQ qualification of
the transfer is required only at the start of the data block, not on each sector.
The block count of sectors to be transferred without intervening interrupts is programmed by the Set-
Multiple-Mode command, which must be executed prior to the Read-Multiple command. When the
Read-Multiple command is issued, the Sector Count register contains the number of sectors (not the
number of blocks or the block count) requested. If the number of requested sectors is not evenly
divisible by the block count, as many full blocks as possible are transferred, followed by a final, partial
block transfer. The partial block transfer is for n sectors, where
n = remainder (sector count/block count).
If the Read-Multiple command is attempted before the Set-Multiple-Mode command has been executed
or when Read-Multiple commands are disabled, the Read-Multiple operation is rejected with an
©2006 Silicon Storage Technology, Inc.
38
S71241-04-000
12/06
Share Link: 