smc256af Numonyx, smc256af Datasheet - Page 62

• Manufacturer Part Number: smc256af
• Description: 32 Mbyte, 64 Mbyte, 128 Mbyte, 256 Mbyte And 512 Mbyte 3.3 V / 5 V Supply Compactflash? Card
• Manufacturer: Numonyx

CF-ATA command description
9.11
9.12
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Read Sector(s) command (20h or 21h)
This command reads from 1 to 256 sectors as specified in the Sector Count register. A
sector count of 0 requests 256 sectors. The transfer begins at the sector specified in the
Sector Number register. When this command is issued and after each sector of data (except
the last one) has been read by the host, the card sets BSY, puts the sector of data in the
buffer, sets DRQ, clears BSY, and generates an interrupt. The host then reads the 512
bytes of data from the buffer.
If an error occurs, the read terminates at the sector where the error occurred. The
Command Block registers contain the cylinder, head, and sector number of the sector
where the error occurred. The flawed data is pending in the sector buffer.
the Read Sector command byte sequence.
Table 59.
Read Verify Sector(s) command (40h or 41h)
This command is identical to the Read Sectors command, except that DRQ is never set and
no data is transferred to the host. When the command is accepted, the card sets BSY.
When the requested sectors have been verified, the card clears BSY and generates an
interrupt.
If an error occurs, the verify terminates at the sector where the error occurs. The Command
Block registers contain the cylinder, head and sector number of the sector where the error
occurred. The Sector Count register contains the number of sectors not yet verified.
Table 60
Cyl Low (4)
Feature (1)
Command
Sect Num
C/D/H (6)
Sect Cnt
Cyl High
Bit
(7)
(5)
(3)
(2)
defines the Read Verify Sector command byte sequence.
Read Sector(s)
1
7
LBA
6
5
1
Drive
4
Cylinder High (LBA 23-16)
Sector Number (LBA 7-0)
Cylinder Low (LBA 15-8)
3
Sector Count
20h or 21h
X
2
Head (LBA 27-24)
1
Table 59
SMCxxxAF
defines
0