XRT94L31
119
REV. 1.0.1
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC
NOTE: The values for t15, t16 and t17 can be found in
1.6
TRANSMIT POH OVERHEAD INPUT PORT
The Transmit POH Overhead Input Port is used to insert the users own value for the POH bytes into either the
outbound STS-1 SPE data-stream (which is output via the Transmit STS-3/STM-1 data-stream or via the
outbound STS-1 SPE data-stream (which is output via the Transmit STS-1 data-stream).
NOTE: The TxPOHIns and the TxPOH input pins are sampled (by the Transmit POH Overhead Input Port) upon the rising
edge of TxPOHClk. All of the remaining signals (e.g., TxPOHFrame and TxPOHEnable) are updated upon the
falling edge of TxPOHClk.
The timing wave-form and information for the Transmit POH Overhead Input Port is presented below.
FIGURE 22. ILLUSTRATION OF TIMING WAVE-FORM OF THE TRANSMIT TOH OVERHEAD INPUT PORT
TABLE 23: TIMING INFORMATION FOR THE TRANSMIT TOH OVERHEAD INPUT PORT
SYMBOL
DESCRIPTION
MIN.
TYP.
MAX.
t15
Falling edge of TxTOHClk to rising edge of TxTOHFrame and TxTOHEn-
able output delay
-0.5ns
0.6ns
t16
TxTOHIns to rising edge of TxTOHClk set-up time
4ns
t17
TxTOH Data to rising edge of TxTOHClk set-up time
4ns
TxTOH
TxTOHIns
TxTOHClk
TxTOHFrame
TxTOHEnable
t15
t16
t17