MB86967 Datasheet, PDF (64/129 Pages) Fujitsu Component Limited. – LAN Controller with PC Card, ISA Bus, and General-purpose Bus Interfaces

MB86967
4. Common Memory Space
Common memory space can be used if the capacity of E²PROM or flash ROM to be selected is large. The
address space is located higher than the CIS (card attribute data register) of attribute memory space (See
examples of E²PROM and flash ROM in 2).
Only even addresses are used in the CIS, but both common memory space even and odd addresses can be
used in common memory space. Only byte access (8 bits) is available.
Writing to common memory space is possible. Efficient writing is performed by data-polling the selected E²PROM
or flash ROM. However, in this case, the PwrDwn bit of CCR1 must be not set for the power-down state without
ending writing.
Batch erase should not be selected for flash ROM. When erasing common memory in blocks, take care not to
erase attribute memory space.
(1) Read from Common Memory
Mode
REG CE2 CE1 OE
Byte access
(8 bits)
1
1
0
0
Word access
(16 bits)
1
0
0
0
High byte only 1
0
1
0
WE PA0
0
1
1
1
×
1
×
PD8 to
PD15
Invalid
Invalid
Invalid
Invalid
PD0 to
PD7
Even byte
Odd byte
ROMS
L
L
ROMRD ROMAD
L
L
L
L
Invalid
H
H
L
Invalid
H
H
L
(2) Write to Common Memory
Mode
REG CE2 CE1 OE
Byte access
(8 bits)
1
1
0
0
Word access
(16 bits)
1
0
0
0
High byte only 1
0
1
0
WE PA0
PD8 to
PD15
PD0 to
PD7
ROMS ROMRD ROMAD
0 Don’t care Even byte L
H
L
1
1 Don’t care Odd byte
L
H
L
1
× Don’t care Don’t care H
H
L
1
× Don’t care Don’t care H
H
L
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