91C94 Datasheet, PDF (35/120 Pages) SMSC Corporation – ISA/PCMCIA SINGLE CHIP ETHERNET CONTROLLER WITH RAM

BANK SELECT REGISTER
OFFSET
E
HIGH
BYTE
0
0
LOW
BYTE
X
NAME
BANK SELECT REGISTER
TYPE
READ/WRITE
SYMBOL
BSR
0
1
1
0
0
1
1
0
1
1
0
0
1
1
BS2
BS1
BS0
X
X
X
X
0
0
0
BS2, BS1, BS0 - Determine the bank presently
in use.
This register is always accessible and is used to
select the register bank in use.
The upper byte always reads as 33h and can be
used to help determine the I/O location of the
LAN91C94.
BS2
BS1
0
0
0
0
0
1
0
1
1
X
The BANK SELECT REGISTER is always
accessible regardless of the value of BS0-2.
The LAN91C94 implements only 4 banks,
therefore accesses to non-existing banks
(BS2=1) are ignored. BS1 and BS0 determine
the bank presently in use.
BS0
BANK#
0
0
1
1
0
2
1
3
X
None
35