Datasheet

SLCFxxxM2TU(I)(-x) CompactFlash Card
Datasheet
61000-07000-106, May 2011 55
6.2 Task File Registers
Table 29: CF Card Task File Registers
Task File Register
Description
Data Register
The Data Register is a 16-bit read/write register used for transferring data
between the CF Card and the host. This register can be accessed in word
mode and byte mode.
Error Register
The Error Register is a read-only register that is used for analyzing an error.
This register is valid when the BSY bit in the Status register and Alternate
Status register are set to ―0‖ (Ready). Diagnostic Codes are returned in the
Error Register after an EXECUTE DRIVE DIAGNOSTIC command (code 90h).
Extended Error Codes returned in the Error Register after a REQUEST SENSE
command (code 03h).
Sector Count Register
This register contains the numbers of sectors of data requested to be
transferred on a read or write operation between the host and the CF Card. If
the value in the register is 0, a count of 256 sectors is indicated.
Sector Number Register
When the LBA bit in the Drive/Head register is 0, this register contains the
starting sector number for any media access. When the LBA bit is set to 1, this
register contains bits 7:0 of the LBA for any media access.
Cylinder Low Register
In CHS mode (LBA=0), this register contains the low-order bits of the starting
cylinder address. In LBA mode, it contains bits 15:8 of the LBA.
Cylinder High Register
In CHS mode (LBA=0), this register contains the high-order bits of the starting
cylinder address. In LBA mode, it contains bits 23:16 of the LBA.
Drive/Head Register
This register selects the CF Card address translation (CHS or LBA) and
provides head address (CHS) or high-order address bits 27:24 for LBA.
Status Register
This read-only register indicates status of a command execution. When the
BSY bit is ―0‖, the other bits are valid; when the BSY bit is ―1‖, the other bits
are not valid. When the register is read, the interrupt pin is cleared.
Alternate Status Register
This register is the same as the Status register, except that is not negated
when the register is read.
Device Control Register
This write-only register is used for controlling the interrupt request and issuing
an ATA soft reset to the CF Card.
Drive Address Register
This read-only register is used for confirming the CF Card’s status. This
register is provided for compatibility with the AT disk drive interface and it is
not recommended that this register be mapped into the host’s I/O space
because of potential conflicts on bit 7.
Command Register
This write-only register is used for writing the command that executes the CF
Card’s operation. The command code is written in the command register after
its parameters are written in the Task File during the CF Card ready state.