KSZ9021GN TR Micrel Inc, KSZ9021GN TR Datasheet - Page 22

• Manufacturer Part Number: KSZ9021GN TR
• Description: Specifications: Number of Drivers/Receivers: 8/8 ; Type: Transceiver ; Voltage - Supply: 3.135 V ~ 3.465 V ; Package / Case: 64-VFQFN Exposed Pad ; Packaging: Tape & Reel (TR) ; Protocol: Gigabit Ethernet ; Lead Free Status: Lead Free ; RoHS Stat
• Manufacturer: Micrel Inc

Micrel, Inc.
GMII Signal Definition
The following table describes the GMII signals. Refer to Clause 35 of the IEEE 802.3 Specification for more detailed
information.
GMII Signal Diagram
The KSZ9021GN GMII pin connections to the MAC are shown in the following figure.
September 2010
GMII
Signal Name
(per spec)
GTX_CLK
TX_EN
TXD[7:0]
TX_ER
RX_CLK
RX_DV
RXD[7:0]
RX_ER
CRS
COL
GMII
Signal Name
(per KSZ9021GN)
GTX_CLK
TX_EN
TXD[7:0]
TX_ER
RX_CLK
RX_DV
RXD[7:0]
RX_ER
CRS
COL
Figure 4. KSZ9021GN GMII Interface
Table 3. GMII Signal Definition
Pin Type
(with respect
to PHY)
Input
Input
Input
Input
Output
Output
Output
Output
Output
Output
Pin Type
(with respect
to MAC)
Output
Output
Output
Output
Input
Input
Input
Input
Input
Input
22
Description
(125MHz for 1000Mbps)
Transmit Data [7:0]
Transmit Error
(125MHz for 1000Mbps)
Receive Data Valid
Receive Data [7:0]
Receive Error
Carrier Sense
Collision Detected
Transmit Reference Clock
Transmit Enable
Receive Reference Clock
M9999-091010-1.1
KSZ9021GN