EZ80F91MCU Datasheet, PDF (259/396 Pages) Zilog, Inc. – eZ80Acclaim-TM Flash Microcontrollers

eZ80F91 MCU
Product Specification
240
Ethernet Media Access Controller
The Ethernet Media Access Controller (EMAC) is a full-function 10/100 Mbps
media access control module with a Media-Independent Interface (MII). This
EMAC and interface combination is called a EMACMII module. Figure 47 pre-
sents an illustration of the EMAC block.
MDIO
MDC
TxD
TxCLK
TxER
TxEN
COL
CRS
MII Interface
RxD
RxCLK
RxDV
RxER
TxFIFO
TxDMA
RxD
RxD/CTRL
RxFIFO
Accept
CTRL
Reject
RxDMA
Figure 47. EMAC Block Diagram
The EMACMII module consists of six submodules that represent the Transmit and
Receive portions of the Ethernet MAC, plus the EMAC sublayer module. In addi-
tion, there is a host interface module, a central clock and reset module, and an MII
management module. There are many different applications possible, including
network interface designs, Ethernet switching designs, and test equipment
designs.
The EMAC functions are contained in the Transmit and Receive modules. These
modules represent the core MAC. 802.3x flow control implemented by the EMAC
sublayer module.
The MII management module provides a two-wire control/status path to the MII
PHY. Read and Write communication to and from registers within the PHY is
accomplished via the host interface.
PS019209-0504
PRELIMINARY
Ethernet Media Access Controller