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XRT94L43
279
SONET/SDH OC-12 TO 12XDS3/E3 MAPPER
REV. 1.0.2
GENERAL PURPOSE INPUT/OUTPUT
PIN #
SIGNAL NAME
I/O
SIGNAL
TYPE
DESCRIPTION
A19
GPIO_0
ExtLOS_0
SSE_CLK
I/O
TTL/
CMOS
General Purpose Input/Output Pin or External LOS Input Pin/Slow-
Speed Interface - Egress - Clock I/O:
The function of this input pin depends on whether or not Channel 0 of
the DS3/E3 Framer Block is enabled or whether or not the Slow-Speed
Interface is enabled.
GPIO_0 (DS3/E3 Framer Block - Channel 0 is disabled).
If the DS3/E3 Framer Block is disabled, then this pin will function as a
General Purpose Input/Output pin.
This input pin can be configured to function as either an input or output
pin by writing the appropriate value into Bit 0 (GPIO_DIR_0), within the
Operation General Purpose Input/Output Direction Register - 0 (Indirect
Address = 0x00, 0x4B), (Direct Address = 0x014B).
When configured as an input pin, the state of this pin can be monitored
by reading the state of Bit 0 (GPIO_0) within the Operation General Pur-
pose Input/Output Register - Byte 0 (Indirect Address = 0x00, 047),
(Direct Address = 0x0147).
When configured as an output pin, the state of this pin can be controlled
by writing the appropriate value into Bit 0 (GPIO_0) within the Operation
General Purpose Input/Output Register - Byte 0 (Indirect Address =
0x00, 0x47), (Direct Address = 0x047).
ExtLOS_0 (DS3/E3 Framer Block - Channel 0 is enabled).
If the DS3/E3 Framer Block is enabled, then this pin will function as the
External LOS Input pin for Channel 0. This input pin is intended to be
connected to a LOS output pin of a DS3/E3 LIU IC.
If this input pin is pulled "High", then the corresponding DS3/E3 Framer
block will automatically declare an LOS condition.
SSE_CLK (Slow-Speed Interface - Egress Port is enabled):
If the Slow-Speed Interface - Egress (SSE) Port is enabled, then this pin
will function as either the SSE_CLK output pin or the SSE_CLK input
pin.
If the user configures the SSE port to operate in the "Insert" Mode, then
the SSE port will be configured to replace any "user-selected" Egress
DS3/E3 or STS-1 data-stream (within the XRT94L43 device) with the
data that is applied to the SSE_POS and SSE_NEG input pins. More
specifically, in the Insert Mode, this pin will function as the SSE_CLK
input pin. In this case, the SSE port will sample and latch the contents of
the SSE_POS and SSE_NEG input pins upon the falling edge of this
input clock signal.
If the user configures the SSE port to operate in the "Extract" Mode, then
the SSE port will output any "user-selected" Egress DS3/E3 or STS-1
signal (within the XRT94L43 device) via this output port. More specifi-
cally, in the "Extract Mode", this pin will function as the SSE_CLK output
pin. In this case, the SSE port will output the data (via the SSE_POS
and SSE_NEG output pins) upon the rising edge of this output clock sig-
nal.