120
Figure 43. Transmit Overhead Clock and Data Alignment
The transmit overhead clock and data alignment timing diagram (Figure 43) shows the relationship
between the TX_E1_DATA, TX_E2_DATA and TX_F1_DATA serial data inputs and their associated clock
TX_E1E2F1_CLK. It is a 72 kHz 50% duty cycle clock that is gapped to produce a 64 kHz nominal rate
and is aligned as shown.
TX_FRAME_SFP
TX_E1E2F1_CLK
TX_E1_DATA
TX_SONETCLK
E1, F1, E2
APPROX. 750 ns
B1
B2
B3
B4
B5
B6
B7
B8
TX_FRAME_SFP
TX_E1E2F1_CLK