SanDisk 20-10-00038 Computer Drive User Manual


 
Interface Description SanDisk CompactFlash Card OEM Product Manual
Decoding for the configuration registers is defined in Table 3-18.
Table 3-18 Configuration Registers Decoding
-CE2
X
-CE1
0
-REG
0
-OE
0
-WE
1
A10
0
A9
1
A8-
A4
00
A3
0
A2
0
A1
0
A0
0
Selected Register
Configuration Option Read
X 0 0 1 0 0 1 00 0 0 0 0 Configuration Option Write
X 0 0 0 1 0 1 00 0 0 1 0 Card Status Read
X 0 0 1 0 0 1 00 0 0 1 0 Card Status Write
X 0 0 0 1 0 1 00 0 1 0 0 Pin Replacement Read
X 0 0 1 0 0 1 00 0 1 0 0 Pin Replacement Write
X 0 0 0 1 0 1 00 0 1 1 0 Socket and Copy Read
X 0 0 1 0 0 1 00 0 1 1 0 Socket and Copy Write
3.4.1 Attribute Memory Function
Attribute Memory is a space where a CompactFlash Memory Card identification and
configuration information is stored, and is limited to 8-bit wide accesses only at even
addresses. The card configuration registers are also located there.
For the Attribute Memory Read function, signals -REG and -OE must be active and -WE
inactive during the cycle. As in the Main Memory Read functions, the signals -CE1 and -CE2
control the even-byte and odd-byte address, but only the even-byte data is valid during the
Attribute Memory access. Refer to Table 3-19 for signal states and bus validity for the
Attribute Memory function.
NOTE: The -CE signal or both the -OE and -WE signal must be de-asserted
between consecutive cycle operaitons.
Table 3-19 Attribute Memory Function
Function Mode -REG -CE2 -CE1 A9 A0 -OE -WE D15-D8 D7-D0
Standby X H H X X X X High Z High Z
Read Byte Access CIS ROM
(8 bits)
L H L L L L H High Z Even
Byte
Write Byte Access CIS (8 bits)
(Invalid)
L H L L L H L Dont
Care
Even
Byte
Read Byte Access
Configuration (8 bits)
L H L H L L H High Z Even
Byte
Write Byte Access
Configuration (8 bits)
L H L H L H L Dont
Care
Even
Byte
Read Word Access CIS
(16 bits)
L L L L X L H Not Valid Even
Byte
Write Word Access CIS
(16 bits) (Invalid)
L L L L X H L Dont
Care
Even
Byte
Read Word Access
Configuration (16 bits)
L L L H X L H Not Valid Even
Byte
Write Word Access
Configuration (16 bits)
L L L H X H L Dont
Care
Even
Byte
02/07, Rev. 12.0 3-22 © 2007 SanDisk Corporation