TXC-06880BIOG Transwitch Corporation, TXC-06880BIOG Datasheet - Page 15

• Manufacturer Part Number: TXC-06880BIOG
• Manufacturer: Transwitch Corporation

Specifications of TXC-06880BIOG

• Operating Supply Voltage (typ): 1.8/3.3V
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Not Compliant

PRELIMINARY TXC-06880-MB, Ed. 4
February 2005
2.1.5 Management Media Independent Interface (MMII) Port
Figure 6. SMII (10/100 Mbit/s) Interface Connection
The MMII port on the Envoy-CE2 is used to configure and retrieve status from the Ethernet
PHYs connected to the Envoy-CE2. Multiple PHY devices (up to 32) are programmable via
this interface. The Envoy-CE2 MMII interface is compliant to the Management interface
outlined in IEEE 802.3u. The device can be configured for preamble suppression at the MMII
interface. The frequency of the output clock of the MMII port (MDC) is programmable to
UPCLK/n (n = 4, 6, 8, 10, 14, 20, or 28). All data transfers are synchronous to the clock signal
and provide support for up to 32 PHYs.
Two additional functions performed by the interface are the Scan function and the Automatic
PHY address Increment function. In Scan mode, multiple back-to-back reads can be
performed from a particular PHY. When Scan mode and Auto PHY address increment are
enabled, back-to-back reads can be performed with the PHY address being incremented
after each read. Hence, the PHYs are scanned.
Note: When Scan mode and Auto PHY address increment are enabled, the range of
addresses scanned will be between “PHY Address” (Register 0x0048 Bits(8-12)) and PHY
number 31.
Notes:
1. When Scan mode and Auto PHY address increment are enabled, the range of addresses
2. Envoy’s Management Media Independent Interface (MMII) is in Master mode.
scanned will be between “PHY Address” (Register 0x0048 Bits 8-12) and PHY number 31.
Note: Series termination resistor values are dependent on the selection of the Ethernet PHY.
Please consult the specification for the Ethernet PHY to determine the series termination resistor values
SMIIREFCLK(A,B)
G(A,B)MTXCLK
G(A,B)TXCLKO
G(A,B)TXCLKI
G(A,B)RXCLK
SSYNCOUT
G(A,B)TXEN
G(A,B)TXER
TX[0-3](A,B)
TX[4-7](A,B)
G(A,B)RXDV
G(A,B)RXER
RX[0-3](A,B)
RX[4-7](A,B)
G(A,B)COL
G(A,B)CRS
- Functional Description -
125 MHz Oscillator
125 MHz Reference Clock
SYNC
TxData[0-3]
TxData[4-7]
GMII 125 MHz TxClk
TxEnable
TxError
RxClk (2.5/25/125 MHz)
RxData[0-3]
RxData[4-7]
RxDataValid
RxError
Collision (Half Duplex Only)
Carrier (CRS) (Half Duplex Only)
MII 2.5/25 MHz Clock
Envoy-CE2 Device
DATA SHEET
TXC-06880
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