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XRT94L43
167
SONET/SDH OC-12 TO 12XDS3/E3 MAPPER
REV. 1.0.2
STS-3/STM-1 TELECOM BUS INTERFACE - TRANSMIT DIRECTION
PIN #
SIGNAL NAME
I/O
SIGNAL
TYPE
DESCRIPTION
E15
STS3TxA_CLK_0
TxSBCLK_0
DMO_0
I
TTL
STS-3 Transmit Telecom Bus Clock Input/STM-1 Sub-Rate
Clock/DMO_0 (General Purpose) input Pin:
The function of this input pin depends upon whether or not theSTS-3/
STM-1 Telecom Bus Interface for Channel 0 has been enabled.
If STS-3/STM-1 Telecom Bus (Channel 0) has been enabled -
STS-3 Transmit Telecom Bus Transmit Clock Input - Channel 0:
This input clock signal functions as the clock source for the STS-3/
STM-1 Transmit Telecom Bus, associated with Channel 0. All input
signals (e.g., STS3TxA_ALARM_0, STS3TxA_D_0[7:0],
STS3TxA_DP_0, STS3TxA_PL_0, STS3TxA_C1J1_0) are sampled
upon the falling edge of this input clock signal.
This clock signal should operate at 19.44MHz.
If STS-3/STM-1 Telecom Bus (Channel 0) is disabled - DMO_0
(General Purpose) Input Pin:
This input pin can be used as a general purpose input pin.
The state of this input pin can be determined by reading the state of
Bit 2 (DMO) within the Line Interface Scan Register associated with
Channel 0 (Address = 0x1E, 0x81), (Direct Address = 0x1F81).
NOTE:
For Product Legacy purposes, this pin is called DMO_0,
because one possible application is to tie this input pin to a
DMO (Drive Monitor Output) output pin, from one of Exar's
XRT73L0X/XRT75L0X
DS3/E3/STS-1
LIU
devices.
However, this input pin, and the corresponding register bit
can be used for any purpose.
C26
STS3TxA_CLK_1
TxSBCLK_1
DMO_1
I
TTL
STS-3 Transmit Telecom Bus Clock Input/STM-1 Sub-Rate
Clock/DMO_1 (General Purpose) input Pin:
The function of this input pin depends upon whether or not theSTS-3/
STM-1 Telecom Bus Interface for Channel 1 has been enabled.
If STS-3/STM-1 Telecom Bus (Channel 1) has been enabled -
STS-3 Transmit Telecom Bus Clock Input - Channel 1:
This input clock signal functions as the clock source for the STS-3/
STM-1 Transmit Telecom Bus, associated with Channel 1. All input
signals, (e.g., STS3TxA_ALARM_1, STS3TxA_D_1[7:0],
STS3TxA_DP_1, STS3TxA_PL_1, STS3TxA_C1J1_1) are sampled
upon the falling edge of this input clock signal.
This clock signal should operate at 19.44MHz.
If STS-3/STM-1 Telecom Bus (Channel 1) is disabled - DMO_1
(General Purpose) Input Pin:
This input pin can be used as a general purpose input pin.
The state of this input pin can be determined by reading the state of
Bit 2 (DMO) within the Line Interface Scan Register associated with
Channel 1 (Address = 0x2E, 0x81), (Direct Address = 0x2F81).
NOTE:
For Product Legacy purposes, this pin is called DMO_1
because one possible application is to tie this input pin to a
DMO (Drive Monitor Output) output pin, from one of Exar's
XRT73L0X/XRT75L0X
DS3/E3/STS-1
LIU
devices.
However, this input pin, and the corresponding register bit
can be used for any purpose.