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TC9204M
Preliminary Data Sheet
10.4.5
Data Read Register
Confidential.
44/49
July 29, 2003
Copyright © 2003, IC Plus Corp.
TC9204M-DS-R05
- Address: 76h, 75h
7 6 5 4 3 2 1 0
DataReadReg
DataReadReg
15 14 13 12 11 10 9 8
76h
75h
Bit(s)
Field
Description
15 – 0
DataReadReg
MDIO Data Read Register
DataReadReg
– Contains a 16 bit data word read from a PHY management register.
Write Operation.
Before starting a write operation the following registers need to be set :
PhyAddress
– written with MDIO device address
RegAddress
– written with MDIO register address
DataWriteReg
– data word to be write to selected register
The write operation is then started by performing a write to IOControl register with bit 0 cleared.
Read Operation.
Before starting a read operation the following registers need to be set :
PhyAddress
– written with MDIO device address
RegAddress
– written with MDIO register address
The write operation is then started by performing a write to IOControl register with bit 0 set.
Subsequently, the IOControl register needs to be monitored in order to detect MDIO operation error
reported via IOControl’s bit 2. The ValidDataRead bit is always read as ‘1’ unless the EEPROM line is
driven at over 1MHz speed. If no error occurred then data can be read from DataReadReg.