Datasheet

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2.0 Pin Description (Continued)
DP83816
Note: MII is normally in TRI-STATE, unless enabled by CFG:EXT_PHY. See Section 4.2.2.
Media Independent Interface (MII)
Symbol
LQFP Pin
No(s) Dir Description
COL 28 I Collision Detect: The COL signal is asserted high asynchronously by the external
PMD upon detection of a collision on the medium. It will remain asserted as long as
the collision condition persists.
CRS 29 I Carrier Sense: This signal is asserted high asynchronously by the external PMD
upon detection of a non-idle medium.
MDC 5 O Management Data Clock: Clock signal with a maximum rate of 2.5 MHz used to
transfer management data for the external PMD on the MDIO pin.
MDIO 4 I/O Management Data I/O: Bidirectional signal used to transfer management
information for the external PMD. (See Section 3.12.4 for details on connections
when MII is used.)
RXCLK 6 I Receive Clock: A continuous clock, sourced by an external PMD device, that is
recovered from the incoming data. During 100 Mb/s operation RXCLK is 25 MHz
and during 10 Mb/s this is 2.5 MHz.
RXD3/MA9,
RXD2/MA8,
RXD1/MA7,
RXD0/MA6
12,
11,
10,
7
I
O
Receive Data: Sourced from an external PMD, that contains data aligned on nibble
boundaries and are driven synchronous to RXCLK. RXD[3] is the most significant
bit and RXD[0] is the least significant bit.
BIOS ROM Address: During external BIOS ROM access, these signals become
part of the ROM address.
RXDV/MA11 15 I
O
Receive Data Valid: Indicates that the external PMD is presenting recovered and
decoded nibbles on the RXD signals, and that RXCLK is synchronous to the
recovered data in 100 Mb/s operation. This signal will encompass the frame,
starting with the Start-of-Frame delimiter (JK) and excluding any End-of-Frame
delimiter (TR).
BIOS ROM Address: During external BIOS ROM access, this signal becomes part
of the ROM address.
RXER/MA10 14 I
O
Receive Error: Asserted high synchronously by the external PMD whenever it
detects a media error and RXDV is asserted in 100 Mb/s operation.
BIOS ROM Address: During external BIOS ROM access, this signal becomes part
of the ROM address.
RXOE 13 O Receive Output Enable: Used to disable an external PMD while the BIOS ROM is
being accessed.
TXCLK 31 I Transmit Clock: A continuous clock that is sourced by the external PMD. During
100 Mb/s operation this is 25 MHz +/- 100 ppm. During 10 Mb/s operation this clock
is 2.5 MHz +/- 100 ppm.
TXD3/MA15,
TXD2/MA14,
TXD1/MA13,
TXD0/MA12
25,
24,
23,
22
O
O
Transmit Data: Signals which are driven synchronous to the TXCLK for
transmission to the external PMD. TXD[3] is the most significant bit and TXD[0] is
the least significant bit.
BIOS ROM Address: During external BIOS ROM access, these signals become
part of the ROM address.
TXEN 30 O Transmit Enable: This signal is synchronous to TXCLK and provides precise
framing for data carried on TXD[3-0] for the external PMD. It is asserted when
TXD[3-0] contains valid data to be transmitted.