78Q2123/78Q2133 MicroPHY™
10/100BASE-TX Transceiver
MR24: MDI/MDIX Control Register
BIT
SYMBOL
TYPE DEFAULT DESCRIPTION
24.15:8
Reserved
R
0
1
Reserved
24.7
PD_MODE
R/W
Write a ‘1’ to this bit to add Parallel Detect mode. This will allow
auto-switching to work when auto-negotiation is off while the
other device has it on.
24.6
24.5
AUTO_SW
MDIX
R/W
R/W
1
0
Write a ‘1’ to this bit to enable auto switching.
Indicates state of the MDI pair or force configuration:
1 = MDIX (cross over)
0 = MDI
When auto_sw is a ‘1’, this bit will only be readable. When
auto_sw is a ‘0’ this bit can be written to set the configuration.
Indicates completion of auto-switch sequence.
1 = Sequence completed
24.4
MDIX_CM
MDIX_SD
R
0
0 = Sequence in progress or auto-switch is disabled.
24.3:0
R/W
<0000> Write initial pattern seed for switching algorithm. The initial
seed directly affects attempts [5,4] respectively to write bits [3:0].
Setting to [0000] will result in device using its own seed of [0101].
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© 2009 Teridian Semiconductor Corporation
Rev 1.5