KC705 Evaluation Board
37
UG810 (v1.3) May 10, 2013
Feature Descriptions
On power-up, or on reset, the PHY is configured to operate in GMII mode with PHY
address
0b00111
using the settings shown in
. These settings can be overwritten
via software commands passed over the MDIO interface.
SGMII GTX Transceiver Clock Generator
[
, callout
An Integrated Circuit Systems ICS844021I chip (U2) generates a high-quality, low-jitter,
125 MHz LVDS clock from a 25 MHz crystal (X3). This clock is sent to FPGA U1, bank 117
GTX transceiver (clock pins G8 (P) and G7 (N)) driving the SGMII interface. Series AC
coupling capacitors are present to allow the clock input of the FPGA to set the common
mode voltage.
shows the Ethernet SGMII clock source.
Table 1-16:
PHY Default Interface Mode
Mode
Jumper Settings
J29
J30
J64
GMII/MII to copper
(default)
Jumper over pins 1-2
Jumper over pins 1-2
No jumper
SGMII to copper,
no clock
Jumper over pins 2-3
Jumper over pins 2-3
No jumper
RGMII
Jumper over pins 1-2
No jumper
Jumper on
Table 1-17:
Board Connections for PHY Configuration Pins
Pin
Connection on
Board
Bit[2]
Definition and Value
Bit[1]
Definition and Value
Bit[0]
Definition and Value
CFG0
V
CC
2.5V
PHYADR[2] = 1
PHYADR[1] = 1
PHYADR[0] = 1
CFG1
Ground
ENA_PAUSE = 0
PHYADR[4] = 0
PHYADR[3] = 0
CFG2
V
CC
2.5V
ANEG[3] = 1
ANEG[2] = 1
ANEG[1] = 1
CFG3
V
CC
2.5V
ANEG[0] = 1
ENA_XC = 1
DIS_125 = 1
CFG4
V
CC
2.5V
HWCFG_MD[2] = 1
HWCFG_MD[1] = 1
HWCFG_MD[0] = 1
CFG5
V
CC
2.5V
DIS_FC = 1
DIS_SLEEP = 1
HWCFG_MD[3] = 1
CFG6
PHY_LED_RX
SEL_BDT = 0
INT_POL = 1
75/50
Ω
= 0