TXC-03456 Description
The L4M device maps a 139.264 Mbit/s asynchronous line signal into an AU-4 VC-4/STS-3c SPE signal. The SDH/SONET signal is transmitted via the add bus with timing derived from the drop bus, add bus, or external clock source. The L4M can pensate for up to a frame offset when using external timing and an external C1 pulse.