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XRT94L31
118
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC
REV. 1.0.1
NOTE: The value for t13 and t14 can be found in
1.5
TRANSMIT TOH OVERHEAD INPUT PORT
The Transmit TOH Overhead Input Port is used to insert the users own value for the TOH bytes into the
outbound STS-3/STM-1 data-stream.
NOTE: The TxTOHIns and the TxTOH input pins are sampled (by the Transmit TOH Overhead Input Port) upon the rising
edge of TxTOHClk. All of the remaining signals (e.g., TxTOHFrame and TxTOHEnable) are updated upon the
falling edge of TxTOHClk.
The timing wave-form and information for the Transmit TOH Overhead Input Port is presented below.
FIGURE 21. AN ILLUSTRATION OF THE WAVEFORMS OF THE SIGNALS THAT ARE INPUT VIA THE TRANSMIT STS-1/
STM-0 TELECOM BUS INTERFACE ASSOCIATED WITH CHANNEL 0 (WHEN CONFIGURED TO OPERATE IN THE STS-3/
STM-1 MODE)
TABLE 22: TIMING INFORMATION FOR THE TRANSMIT STS-1/STM-0 TELECOM BUS INTERFACE, FOR CHANNEL 0
WHEN IT HAS BEEN CONFIGURED TO OPERATE IN THE
STS-3/STM-1 MODE
SYMBOL
DESCRIPTION
MIN.
TYP.
MAX.
t13
TxA_D[7:0], TxA_PL, TxA_C1J1, TxA_ALARM and TxA_DP to rising edge
of TxA_CLK set-up time requirements
4ns
t14
Rising edge of TxA_CLK to TxA_D[7:0], TxA_PL, TxA_C1J1, TxA_ALARM
and TxA_DP hold time requirements
0 ns
TxA_CLK
TxA_D[7:0]
TxA_PL
TxA_C1J1
A2
C1
J1
Data
t13
t14