SanDisk CompactFlash Extreme III User Manual
Page 42
Interface Description
SanDisk CompactFlash Card OEM Product Manual
Card Configuration and Status Register (con’t)
Bit
Name
Description
D7
Changed
Indicates that one or both of the Pin Replacement Register CRdy, or
CWProt bits are set to "1". When the Changed bit is set, -STSCHG Pin 46
is held low if the SigChg bit is a "1" and the card is configured for the I/O
interface.
D6
SigChg
This bit is set and reset by the host to enable and disable a state-change
"signal" from the Status Register, the Changed bit control pin 46 the
Changed Status signal. If no state change signal is desired, this bit should
be set to zero "0" and pin 46 (-STSCHG) signal will be held high while the
card is configured for I/O
D5
IOis8
The host sets this bit to a one "1" if the card is to be configured in an 8-bit
I/O mode. The card is always configured for both 8- and 16-bit I/O, so this
bit is ignored.
D2
PwrDwn
This bit indicates whether the host requests the card to be in the power
saving or active mode. When the bit is "1", the card enters a power down
mode. When "0", the host is requesting the card to enter the active mode.
The PCMCIA Rdy/-Bsy value becomes BUSY when this bit is changed.
Rdy/-Bsy will not become Ready until the power state requested has been
entered. The card automatically powers down when it is idle and powers
back up when it receives a command
D1
Int
This bit represents the internal state of the interrupt request. This value is
available whether or not I/O interface has been configured. This signal
remains true until the condition that caused the interrupt request has been
serviced. If interrupts are disabled by the -IEN bit in the Device Control
Register, this bit is a "0".
3.4.4
Pin Replacement Register (Address 204h in Attribute Memory)
The Pin Replacement Register information is described below.
Operation
D7
D6
D5
D4
D3
D2
D1
D0
Read
0
0
CRdy/-Bsy
CWProt
1
1
RRdy/-Bsy
RWProt
Write
0
0
CRdy/-Bsy
CWProt
0
0
MRdy/-Bsy
MWProt
Bit
Name
Description
D5
CRdy/-Bsy
This bit is set to "1" when the bit RRdy/-Bsy changes state. This bit can also
be written by the host.
D4
CWProt
This bit is set to "1" when the RWprot changes state. This bit may also be
written by the host.
D1
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.
MRdy/-Bsy
This bit acts as a mask for writing the corresponding bit CRdy/-Bsy.
D0
RWProt
This bit is always "0" because the card does not have a write-protect
switch. When written, this bit acts as a mask for writing the corresponding
bit CWProt.
MWProt
This bit when written acts as a mask for writing the corresponding bit
CWProt.
02/07, Rev. 12.0
3-24
© 2007 SanDisk Corporation