91C94 Datasheet, PDF (15/120 Pages) SMSC Corporation – ISA/PCMCIA SINGLE CHIP ETHERNET CONTROLLER WITH RAM

8 BIT MODE
((nEN16=1) (16BIT=0))
16 BIT MODE
otherwise
Table 1 - Bus Transactions in ISA Mode
A0
nSBHE
D0-7
0
X
even byte
1
X
odd byte
0
0
even byte
D8-15
-
-
odd byte
0
1
even byte
-
1
0
-
odd byte
1
1
invalid cycle
8 BIT MODE
Table 2 - Bus Transactions in PCMCIA Mode
A0 nCE1
nCE2
D0-7
0
0
X
even byte
D8-15
-
((IOis8=1) +
(nEN16=1).(16BIT=0))
1
0
X
X
1
X
16 BIT MODE
0
0
0
odd byte
NO CYCLE
even byte
-
odd byte
otherwise
0
0
1
1
0
1
X
1
0
X
1
1
even byte
odd byte
-
NO CYCLE
-
odd byte
16BIT: CONFIGURATION REGISTER bit 7
IOis8: CSR register bit 5
nEN16: pin nEN16
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