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IP175A LF
Preliminary Data Sheet
4.4
MII, SMI and MII register
IP175A LF supports two MII and one SMI (MDC and MDIO). Two MII interface to the external MAC for
data transfer and the SMI is used to program switch controller and PHY4.
IP175A LF provides basic MII registers for PHY4 and extended MII registers for switch controller. The
external MAC monitors or configures PHY4 by reading or writing the basic MII registers through SMI. The
external MAC monitors or configures switch controller by reading or writing the extended MII registers
through SMI.
The switch controller can be configured by pin and EEPROM, too. The operation is illustrated in the
following diagrams.
EEPR O M
B a s ic M II
r e gis t er s
E x t e n ded M I I
re g is t e r s
MD C , MD IO
Sw it c h
c o n tr o lle r
PH Y 4
I P 1 75A L F
EEPR O M
re g is t e r s
MA C
MA C
CP U
SC L , SD A
in itia l v a u le
f r om pins
T h r e e w a y s t o c onf ig u r e IP 17 5 A , by pins , E E P R O M , or pr ogr am m ing M I I r egis t er s
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February 20, 2006
Copyright © 2004, IC Plus Corp.
IP175A LF-DS-R08