LAN83C175 Datasheet, PDF (36/92 Pages) SMSC Corporation – Ethernet CARDBUS Integrated Controller With Modem Support

ROM DECODE
ENABLE
1
1
1
1
0
0
0
0
0
0
MEMORY MEM. SPACE
MAP ENABLE ENABLE
X
1
X
1
X
0
X
0
1
1
1
1
1
0
1
0
0
X
0
X
I/O SPACE
ENABLE
1
0
1
0
1
0
1
0
1
0
EXPANSION
ROM
Enabled
Enabled
Disabled
Disabled
Disabled
Disabled
Disabled
Disabled
Disabled
Disabled
CONTROL
REGISTERS
I/O Space
Disabled
I/O Space
Disabled
I/O & Memory
Mem. Space
I/O Space
Disabled
I/O Space
Disabled
After reset, the ROM will be disabled and the
ROM base address will be unknown. The
system POST code will map the ROM into host
memory space, copy its contents into system
RAM and read the CIS structure or execute the
ROM initialization code The ROM must be found
since it contains the mandatory CIS structure for
CardBus functions. The ROM initialization code
is allowed to perform dynamic re-sizing of the
runtime code in order to use as little of the host
memory space as possible.
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