Asynchronously mapping/de-mapping 21 E1 or T1 traffics into/from STM-1. T1 traffic mapping path is T1 VC11 TU12. TEBGA256 Configurable receive and transmit TU12 time-slots via microprocessor -40 ~ 85℃ Detects loss of input clock on Telecom Bus Interprets TU12 pointer according to G.783 (2000/10) and.