FUNCTIONAL DESCRIPTION
The SMC91C95 consists of an integrated Ethernet controller mapped entirely in I/O space, as well as support for an external Modem controller also mapped in I/O space. In addition, PCMCIA attribute memory space is decoded to interface an external CIS ROM, with configuration registers as per PCMCIA 3.X extensions implemented
The Ethernet controller function includes a
Table 1 - Bus Transactions in ISA Mode
| A0 | nSBHE |
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8 BIT MODE | 0 | X | even byte | - |
(nEN16=1) |
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(16 BIT=0) | 1 | X | odd byte | - |
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16 BIT MODE | 0 | 0 | even byte | odd byte |
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otherwise | 0 | 1 | even byte | - |
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| 1 | 0 | - | odd byte |
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| 1 | 1 | invalid cycle | |
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