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CompactFlash Memory Card Product Manual
SanDisk CompactFlash Memory Card Product Manual © 1998 SANDISK CORPORATION 44
4.6 Common Memory Transfer Function
4.6.1 Common Memory Function
The Common Memory transfer to or from the
CompactFlash Memory Card can be either 8 or 16
bits.
The CompactFlash Memory Card permits both 8
and 16 bit accesses to all of its Common Memory
addresses.
The CompactFlash Memory Card may request the
host to extend the length of a memory write cycle
or extend the length of a memory read cycle until
data is ready by asserting the -WAIT signal at
the start of the cycle.
Table 4-16 Common Memory Function
Function Code - R E G - C E 2 - C E 1 A0 - O E - W E D15-D8 D7-D0
Standby Mode X H H X X X High Z High Z
Byte ReadAccess
(8 bits) H
H H
H L
L L
H
L
L H
H High Z
High Z Even-Byte
Odd-Byte
Byte Write Access
(8 bits) H
H H
H L
L L
H
H
H L
L Don't Care
Don't Care Even-Byte
Odd-Byte
Word Read Access
(16 bits) H L L X L H Odd-Byte Even-Byte
Word Write Access
(16 bits) H L L X H L Odd-Byte Even-Byte
Odd Byte Read Only
(8 bits) H L H X L H Odd-Byte High Z
Odd Byte Write Only
(8 bits) H L H X H L Odd-Byte Don't Care