Socket And Copy Register; I/O Transfer Function - SanDisk CompactFlash Product Manual

CompactFlash Memory Card Interface Description
RRdy/-Bsy This bit is used to determine the internal state of the Rdy/-Bsy signal. This bit may be used to determine the
state of the Ready/-Busy as this pin has been reallocated for use as Interrupt Request on an I/O card. When
written, this bit acts as a mask for writing the corresponding bit CRdy/-Bsy.
RWProt This bit is always zero (0) since the CompactFlash Memory Card does not have a Write Protect switch. When
written, this bit acts as a mask for writing the corresponding bit CWProt.
MRdy/-Bsy This bit acts as a mask for writing the corresponding bit CRdy/-Bsy.
MWProt This bit when written acts as a mask for writing the corresponding bit CWProt.
Initial Value of
(C) Status
3.4.5. Socket and Copy Register (Address 206h in Attribute Memory
This register contains additional configuration information. This register is always written by the system before
writing the card's Configuration Index Register.
Operation D7
Read Reserved
Write 0
Reserved This bit is reserved for future standardization. This bit must be set to zero (0) by the software when the
register is written.
Drive # This bit indicates the drive number of the card if twin card configuration is supported.
X The socket number is ignored by the CompactFlash Memory Card.

3.5. I/O Transfer Function

The following sections provide valuable information for the I/O Transfer function.
3-22
Table 3-20. Pin Replacement Changed Bit/Mask Bit Values
Written by Host
"C" Bit
0 X
1 X
X 0
X 1
Table 3-21. Socket and Copy Register Organization
D6 D5
0 0
0 0
®
CompactFlash Memory Card Product Manual, Rev. 10.0 © 2002 SANDISK CORPORATION
Final
"C" Bit
"M" Bit
0 0 Unchanged
0 1 Unchanged
1 0 Cleared by Host
1 1 Set by Host
D4 D3
Drive # 0
Drive # (0) X
Comments
D2 D1 D0
0 0
X X
0
X