39
BANK SELECT REGISTER
OFFSET NAME TYPE SYMBOL
EBANK SELECT
REGISTER READ/WRITE BSR
HIGH
BYTE 00110011
00110011
LOW
BYTE BS2 BS1 BS0
XXXXX000
BS2, BS1, BS0 - Determine the bank presently in
use.
The BANK SELECT REGISTER is always
accessible except in PCMCIA powerdown mode
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
SMC91C95.
The BANK SELECT REGISTER is always
accessible regardless of the value of BS0-BS2.
The SMC91C95 implements only four banks in
ISA mode, therefore, accesses to non-existing
banks (BS2=1) are ignored. All six banks are
accessible in PCMCIA mode.
BS2 BS1 BS0 BANK#
0
0
0
0
1
0
0
1
1
X
0
1
0
1
X
0
1
2
3
None