Collision (E_Col) - Motorola DigitalDNA ColdFire MCF5272 User Manual

Ethernet Module Signals

19.12.3 Collision (E_COL)

The E_COL input is asserted upon detection of a collision and remains asserted while the
collision persists. This signal is not defined for full-duplex mode.
19.12.4 Receive Data Valid (E_RxDV)
Asserting the receive data valid (E_RxDV) input indicates that the PHY has valid nibbles
present on the MII. E_RxDV should remain asserted from the first recovered nibble of the
frame through to the last nibble. Assertion of E_RxDV must start no later than the SFD and
exclude any EOF.
19.12.5 Receive Clock (E_RxCLK)
The receive clock (E_RxCLK) input provides a timing reference for E_RxDV, E_RxD[3:0],
and E_RxER.
19.12.6 Receive Data (E_RxD0)
E_RxD0 is the Ethernet input data transferred from the PHY to the media-access controller
when E_RxDV is asserted. This signal is used for 10-Mbps Ethernet data. This signal is also
used for MII mode Ethernet data in conjunction with E_RxD[3:1].
19.12.7 Transmit Enable (E_TxEN)
The transmit enable (E_TxEN) output indicates when valid nibbles are present on the MII.
This signal is asserted with the first nibble of a preamble and is negated before the first
E_TxCLK following the final nibble of the frame.
19.12.8 Transmit Data (E_TxD[3:1]/PB[10:8])
Ethernet mode: These pins contain the serial output Ethernet data and are valid only during
assertion of E_TxEN in MII mode.
Port B mode: These pins can also be configured as I/O pins PB[10:8].
19.12.9 Receive Data (E_RxD[3:1]/PB[13:11])
Ethernet mode: These pins contain the Ethernet input data transferred from the PHY to the
media-access controller when E_RxDV is asserted in MII mode operation.
Port B mode: These pins can also be configured as I/O pins PB[13:11].
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