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XRT94L43
85
SONET/SDH OC-12 TO 12XDS3/E3 MAPPER
REV. 1.0.2
STS-3/STM-1 TELECOM BUS INTERFACE - RECEIVE DIRECTION
PIN #
SIGNAL NAME
I/O
SIGNAL
TYPE
DESCRIPTION
A20
STS3RxD_CLK_0
RxSBClkLLOOP_0
O
CMOS
Receive STS-3/STM-1 Telecom Bus Clock Output - Channel 0;
LLOOP_0 (General Purpose) Output Pin:
The function of this input pin depends upon whether or not theSTS-3/
STM-1 Telecom Bus Interface associated with Channel 0 is enabled.
If STS-3/STM-1 Telecom Bus (Channel 0) has been enabled - STS-3/
STM-1 Receive Telecom Bus Clock Output - Channel 0;
STS3RxD_CLK_0:
All signals, which is output via the Receive Telecom Bus - Channel 0 is
clocked out upon the rising edge of this clock signal. This includes the fol-
lowing signals.
STS3RxD_D_0[7:0]
STS3RxD_ALARM_0
STS3RxD_DP_0
STS3RxD_PL_0
STS3RxD_C1J1_0
This clock signal will operate at 19.44MHz.
If STS-3/STM-1 Telecom Bus (Channel 0) is disabled - LLOOP_0
(General Purpose) Output Pin:
This output pin can be used as a general purpose output pin.
The state of this output pin can be controlled by writing the appropriate
value into Bit 0 (LLOOP) within the Line Interface Drive Register associ-
ated with Channel 0 (Indirect Address = 0x1E, 0x80), (Direct Address =
0x1F80).
NOTE:
For Product Legacy purposes, this pin is called LLOOP_0
because one possible application is to tie this output pin to an
LLOOP (Local Loop-back) input pin from one of Exar's
XRT73L0X/XRT75L0X DS3/E3/STS-1 LIU devices. However,
this output pin, and the corresponding register bit can be used for
any purpose.