lan91c95 Standard Microsystems Corp., lan91c95 Datasheet - Page 106

• Manufacturer Part Number: lan91c95
• Description: Isa/pcmcia Full Duplex Single-chip Ethernet And Modem Controller With Ram
• Manufacturer: Standard Microsystems Corp.

ISA MODE
The following parameters are obtained from the
EEPROM as board setup information:
All the above mentioned values are read from
the EEPROM upon hardware reset. Except for
the INDIVIDUAL ADDRESS, the value of the
IOS switches determines the offset within the
EEPROM for these parameters, in such a way
that many identical boards can be plugged into
the same system by just changing the IOS
jumpers.
In order to support a software utility based
installation, even if the EEPROM was never
programmed, the EEPROM can be written using
the LAN91C95. One of the IOS combination is
associated with a fixed default value for the key
parameters
INTERRUPT)
regardless of the EEPROM based value being
programmed. This value will be used if all IOS
pins are left open or pulled high.
The EEPROM is arranged as a 64 x 16 array.
The specific target device is the 9346 1024-bit
Serial EEPROM.
done in words. All EEPROM addresses shown
are specified as word addresses.
ETHERNET INDIVIDUAL ADDRESS
I/O BASE ADDRESS
ROM BASE ADDRESS
8/16 BIT ADAPTER
10BASE-T or AUI INTERFACE
INTERRUPT LINE SELECTION
(I/O
that
All EEPROM accesses are
BASE,
can
always
BOARD SETUP INFORMATION
ROM
be
BASE,
used
106
If
ADDRESS
Currently assigned values are assumed for the
other registers. These values are default if the
EEPROM read operation follows hardware
reset.
The EEPROM SELECT bit is used to determine
the type of EEPROM operation: a) normal or b)
general purpose register.
a)
On EEPROM read operations (after reset or
after
CONFIGURATION
REGISTER are updated with the EEPROM
values at locations defined by the IOS2-0 pins.
The
updated
INDIVIDUAL ADDRESS area of the EEPROM.
On EEPROM write operations (after setting the
STORE
CONFIGURATION
REGISTER
locations defined by the IOS2-0 pins.
Configuration
Register
Base Register
NORMAL
EEPROM SELECT bit = 0
IOS2-IOS0=7,
INDIVIDUAL ADDRESS
INDIVIDUAL
REGISTER
setting
with
bit)
is
are
the
EEPROM
read
the
written
RELOAD
ADDRESS
REGISTER
REGISTER
only
values
IOS Value * 4
(IOS Value *4) + 1
from
EEPROM WORD
ADDRESS
in
values
the
OPERATION
stored
the
20-22 hex
the
registers
high)
INDIVIDUAL
and
and
EEPROM.
EEPROM
of
in
BASE
BASE
the
are
the
the
-