CX82100 Home Network Processor Data Sheet
7.9
7-Wire Serial Interface (7-WS)
This mode is enabled by setting bit 7 of the EMAC x Network Access register
(E_NA_{x}). In this mode the MII interface works in serial mode and is designed to
interface to Conexant’s CX24611 HomePNA 2.0 PHY/AFE or to any other GPSI
interface (AMD's "General Purpose Serial Interface," a de facto standard for MAC-to-
10Base-T device interface). All MII signals function the same way as in Ethernet mode
except that the 4-bit data is serialized on pins EMx_TXD0 and EMx_RXD0, and
EMx_TXD0 and EMx_TXEN are driven from the negative edge of EMx_TX_CLK.
Table 7-9 describes the signals for the 7-WS interface.
Table 7-9. 7-WS Interface Signals
7-WS Signal
RXD
MII Signal
EMx_RXD0
Direction
Input
Description
Receive Data.
Receive input bit stream.
Receive Clock.
RCLK
EMx_RX_CLK
Input
A 10 MHz square wave synchronized to the Receive Data and only active
while receiving an input bit stream.
Receive Enable.
A logical input that indicates the presence of carrier on the channel.
Transmit Data.
Transmit output bit stream.
Transmit Clock.
10 MHz clock.
RENA
TXD
EMx_RXCRS
EMx_TXD0
Input
Output
Input
TCLK
TENA
EMx_TX_CLK
EMx_TXEN
Output
Transmit Enable.
Transmit output bit stream enable. While asserted, it enables valid
transmit output (TXD).
CLSN
EMx_COL
Input
Collision.
A logical input that indicates that a collision is occurring on the channel.
101306C
Conexant Proprietary and Confidential Information
7-27
CONEXANT [ CONEXANT SYSTEMS, INC ]
