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XRT94L43
27
SONET/SDH OC-12 TO 12XDS3/E3 MAPPER
REV. 1.0.2
H3
TxLDCC
I
TTL
Transmit - Line DCC Input Port:
This input pin, along with the TxLDCCEnable and the TxTOHClk pins
are used to insert a value for the D4, D5, D6, D7, D8, D9, D10, D11 and
D12 bytes, into the Transmit STS-12 TOH Processor Block. The Trans-
mit STS-12 TOH Processor block will accept this data and insert it into
the D4, D5, D6, D7, D8, D9, D10, D11 and D12 byte-fields, within the
outbound STS-12 data-stream.
Whatever Line DCC HDLC Controller Circuitry is interface to the this
input pin, the TxLDCCEnable and the TxTOHClk is suppose to do the
following.
1. It should continuously monitor the state of the TxLDCCEnable input
pin.
2. Whenever the TxLDCCEnable input pin pulses "High", then the Sec-
tion DCC Interface circuitry should place the next Line DCC bit (to be
inserted into the Transmit STS-12 TOH Processor block) onto the
TxLDCC input pin, upon the falling edge of TxTOHClk.
3. Any data that is placed on the TxLDCC input pin, will be sampled
upon the rising edge of TxTOHClk.
NOTE: Tie this pin to GND, if it is not going to be used.
F4
TxE1F1E2Enable
O
CMOS
Transmit E1-F1-E2 Byte Input Port - Enable (or Ready) Indicator
Output Pin:
This output pin, along with the TxTOHClk output pin and the TxE1F1E2
input pin are used to insert a value for the E1, F1 and E2 bytes, into the
Transmit STS-12 TOH Processor Block. The Transmit STS-12 TOH
Processor block will accept this data and will insert into the E1, F1 and
E2 byte-fields, within the outbound STS-12 data-stream.
Whatever external circuitry (which is connected to the TxTOHClk, the
TxE1F1E2 and this output pin, is suppose to do the following.
1. It should continuously monitor the state of this output pin.
2. Whenever this output pin pulses "High", then the external circuitry
should place the next orderwire bit (to be inserted into the Transmit
STS-12 TOH Processor block) onto the TxE1F1E2 input pin, upon the
falling edge of TxTOHClk.
Any data that is placed on the TxE1F1E2 input pin, will be sampled
upon the rising edge of TxOHClk.
D2
TxE1F2E2Frame
O
CMOS
Transmit E1-F1-E2 Byte Input Port - Framing Output Pin:
This output pin pulses "High" for one period of TxTOHClk, one TxTO-
HClk bit-period prior to the Transmit E1-F1-E2 Byte Input Port expecting
the very first byte of the E1 byte, within a given outbound STS-12 frame.
SONET/SDH OVERHEAD INTERFACE - TRANSMIT DIRECTION
PIN #SIGNAL NAME
I/O
SIGNAL
TYPE
DESCRIPTION