Table 6-14. 4450 RMII modes pin mappings
Pin Name
MAC-MII
PHY-MII
RMII Signal
mii_txen
I/O
RMII Signal
rmii_crs_rdv
rmii_rxd[1:0]
I/O
rmii_bus0[2]
mii_bus0[1:0]
out
out
out
out
mii_txd[1:0]
Note
The RMII Specification allows for rmii_ref_clk to be driven by an external source in
any mode. The 4450 allows for either an input or output.
6.3.1
RMII Connection Diagrams
MAC
4450
ref_clk
rmii_ref_clk
REF_CLK
TXEN
txen
rmii_bus1[2]
txd[1:0]
rmii_bus1[1:0]
TD[1:0]
crs_rdv
rmii_bus0[2]
CRS_RDV
RD[1:0]
rxd[1:0]
rmii_bus0[1:0]
Figure 6-19. RMII PHY Mode
4450 – Data Sheet, DS-0131-06
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