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XRT94L43
177
SONET/SDH OC-12 TO 12XDS3/E3 MAPPER
REV. 1.0.2
B22
STS3TxA_DP_0
TxDS3FP_4
TxSTS1PL_4
I/O
TTL/
CMOS
STS-3/STM-1 Transmit Telecom Bus - Parity Input Pin - Channel
0; DS3/E3 Frame Generator Framing Pulse Input/Output Pin -
Channel 4:
The function of this 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/STM-1 Transmit Telecom Bus - Parity Input Pin:
This input pin can be configured to function as one of the following.
1. The EVEN or ODD parity value of the bits which are input via the
ST3TXA_D_0[7:0] input pins.
2. The EVEN or ODD parity value of the bits which are being input
via the STS3TXA_D_0[7:0] input and the states of the
STS3TXA_PL_0 and STS3TXA_C1J1_0 input pins.
NOTE: Any one of these configuration selections can be made by
writing the appropriate value into the Interface Control
Register - Byte 0 register (Indirect Address = 0x00, 0x3B),
(Direct Address = 0x013B).
If STS-3/STM-1 Telecom Bus (Channel 0) is disabled -
TxDS3FP_4 (Transmit DS3 Frame Pulse Input/Output - Channel
4):
If the STS-3/STM-1 Telecom Bus (Channel 0) is disabled and if the
DS3/E3 Framer block is enabled then this pin will function as either a
Transmit Framing Reference input pin or as a Transmit Framing Ref-
erence output pin.
If the Frame Generator (within the DS3/E3 Framer block) is con-
figured to operate in the Loop-Timing or in the Local-Timing/
Asynchronous Framing Mode:
This pin will function as a Framing Reference Output pin. The Frame
Generator block (associated with Channel 4) will pulse this output pin
"High" for one DS3/E3 bit-period, one period prior to the first bit of a
given DS3 or E3 frame being applied to the DS3/E3/
STS1_DATA_IN_4 input pin.
If the Frame Generator (within the DS3/E3 Framer block) is con-
figured to operate in the Local-Timing/TxDS3FP Mode:
This pin will function as a Framing Reference Input pin. In this mode,
the user is expected to pulse this input pin "High" for one DS3 or E3
bit-period, coincident with the first bit of a given DS3 or E3 frame,
being placed on the DS3/E3/STS1_DATA_IN_4 input pin. The Frame
Generator block (associated with Channel 4) will synchronize its gen-
eration of DS3 or E3 frames to these framing pulses applied to this
input pin.
NOTE: This pin is inactive if the Frame Generator block, associated
with Channel 4 is by-passed.
STS-3/STM-1 TELECOM BUS INTERFACE - TRANSMIT DIRECTION
PIN #SIGNAL NAME
I/O
SIGNAL
TYPE
DESCRIPTION