User`s guide
1.5 General-Purpose Port
The 21140A has an 8-bit, general-purpose port for setting the various operating
modes of the EB140A–TX. CSR12 in the 21140A controls the general-purpose
port.
Figure 1–4 shows the bit mapping of the general-purpose port, and Table 1–2
describes the bit operations.
For detailed information about the general-purpose port, refer to the Digital
Semiconductor 21140A PCI Fast Ethernet LAN Controller Hardware Reference
Manual.
Figure 1–4 General-Purpose Port Bit Mapping
Link
Status
Receive
Activity
Transmit
Activity
Reserved PHY
Reset
ReservedReserved Reserved
Bit
Number
7
Input Input Input Output Output Output Output Output
6543210
LJ03893A.AI5
Preliminary—Subject to Change—July 1996 1–7