Editing Media-independent interface (section)

===Receiver signals===
{| class="wikitable"
|-
! Signal name
! Description
! Direction
|-
| RX_CLK
| Receive clock
| PHY to MAC
|-
| RXD0
| Receive data bit 0 (received first)
| PHY to MAC
|-
| RXD1
| Receive data bit 1
| PHY to MAC
|-
| RXD2
| Receive data bit 2
| PHY to MAC
|-
| RXD3
| Receive data bit 3
| PHY to MAC
|-
| RX_DV
| Receive data valid
| PHY to MAC
|-
| RX_ER
| Receive error
| PHY to MAC
|-
| CRS
| Carrier sense
| PHY to MAC
|-
| COL
| Collision detect
| PHY to MAC
|}

The first seven receiver signals are entirely analogous to the transmitter signals, except RX_ER is not optional and used to indicate the received signal could not be decoded to valid data. The receive clock is recovered from the incoming signal during frame reception. When no clock can be recovered (i.e. when the medium is silent), the PHY must present a free-running clock as a substitute.

The receive data valid signal (RX_DV) is not required to go high immediately when the frame starts, but must do so in time to ensure the "start of frame delimiter" byte is included in the received data. Some of the preamble nibbles may be lost.

Similar to transmit, raising RX_ER outside a frame is used for special signaling. For receive, two data values are defined: 0b0001 to indicate the link partner is in EEE low power mode, and 0b1110 for a ''false carrier'' indication.

The CRS and COL signals are asynchronous to the receive clock, and are only meaningful in half-duplex mode. Carrier sense is high when transmitting, receiving, or the medium is otherwise sensed as being in use. If a collision is detected, COL also goes high while the collision persists.

In addition, the MAC may weakly pull-up the COL signal, allowing the combination of COL high with CRS low (which a PHY will never produce) to serve as indication of an absent/disconnected PHY.