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CHAPTER 2 PIN FUNCTIONS
40
2.3.4 PMD Interface Signals (Internal PHY Mode: PHM of the GMR Register = 0)
The PMD interface is used to connect an optical transceiver/receiver module.
Symbol
Pin No.
I/O
I/O level
Function
RDIT
278
I
P-ECL
True(+)
Receive Serial Data Input
Connect a pull-up resistor when the RDIT pin is not
used.
Receive Serial Data Input
Connect a pull-down resistor when the RDIC pin is not
used.
Receive serial clock input
This pin is used for external clock recovery/synthesizer
connection (PLL of the GMR register = 1).
Connect a pull-up resistor when the RCIT pin is not
used.
Receive serial clock input
This pin is used for external clock recovery/synthesizer
connection (PLL of the GMR register = 1).
Connect a pull-down resistor when the RCIC pin is not
used.
Reference Clock
The REFCLK pin is used to input the system clock
(19.44 MHz) to the internal clock recovery/synthesizer.
Connect a pull-up resistor when the REFCLK pin is not
used.
Transmit Serial Data Output
RDIC
277
I
P-ECL
Complement
(-)
RCIT
(Common with
FULL_B pin)
249
I
P-ECL
True(+)
RCIC
(Common with
EMPTY_B pin)
248
I
P-ECL
Complement
(-)
REFCLK
(Common with
PHINT_B pin)
268
I
TTL
TDOT
273
O
P-ECL
True(+)
P-ECL
Complement
TDOC
274
O
(-)
Transmit Serial Data Output
TFKT
(Common with
Rx0 pin)
242
I
P-ECL
True(+)
Transmit serial clock input
This pin is used for external clock recovery/synthesizer
connection (PLL of the GMR register = 1).
Connect a pull-up resistor when the TFKT pin is not
used.
Transmit serial clock input
This pin is used for external clock recovery/synthesizer
connection (PLL of the GMR register = 1).
Connect a pull-down resistor when the TFKC pin is not
used.
PHY Layer Alarm Detection
The PHYALM signal becomes active high when one or
more internally monitored error states (CMDARM, LOS,
OOF, LOF, LOP, OCD, LCD, Line AIS, Path AIS, Line
RDI, and Path RDI) are detected. One or more error
states to be indicated can be selected using the internal
AMR1 and AMR2 registers.
Signal Detect
The SD pin is used to input the signal detect signal (LOS
detection, etc.) of the PMD device. When a low level is
input to SD, the
μ
PD98405 assumes LOS detection.
Connect a pull-up resistor when the SD pin is not used.
TFKC
(Common with
Rx1 pin
)
241
I
P-ECL
Complement
(-)
PHYALM
(Common with
PHR/W_B pin)
266
O
TTL
SD
(Common with
PHCE_B pin
)
267
I
TTL