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XRT94L43
180
REV. 1.0.2
SONET/SDH OC-12 TO 12XDS3/E3 MAPPER
AE19
STS3TxA_DP_3
TxDS3FP_7
TxSTS1PL_7
I/O
TTL/
CMOS
STS-3/STM-1 Transmit Telecom Bus - Parity Input Pin - Channel
3; DS3/E3 Frame Generator Framing Pulse Input/Output Pin -
Channel 7:
The function of this pin depends upon whether or not theSTS-3/STM-
1 Telecom Bus Interface for Channel 3 has been enabled.
If STS-3/STM-1 Telecom Bus (Channel 3) 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_3[7:0] input pins.
2. The EVEN or ODD parity value of the bits which are being input
via the STS3TXA_D_3[7:0] input and the states of the
STS3TXA_PL_3 and STS3TXA_C1J1_3 input pins.
NOTE: Any one of these configuration selections can be made by
writing the appropriate value into the Interface Control
Register - Byte 3 register (Indirect Address = 0x00, 0x38),
(Direct Address = 0x0138).
If STS-3/STM-1 Telecom Bus (Channel 0) is disabled -
TxDS3FP_7 (Transmit DS3 Frame Pulse Input/Output - Channel
7):
If the STS-3/STM-1 Telecom Bus (Channel 3) 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 7) 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_7 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_7 input pin. The Frame
Generator block (associated with Channel 7) 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 7 is by-passed.
STS-3/STM-1 TELECOM BUS INTERFACE - TRANSMIT DIRECTION
PIN #SIGNAL NAME
I/O
SIGNAL
TYPE
DESCRIPTION