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ACARS CMU Simulator
Square Peg Communications Inc. (SPCI)
The SPCI CMU Simulator replaces the ACARS Communications Management Unit for end-to-end testing of the ACARS system. It communicates with an Inmarsat Classic Aero or SB-Safety Satellite Data Unit (SDU) via ARINC-429 to generate and receive ACARS traffic. The CMU Simulator is implemented as a Physical Layer Tester script, and can run on either a BPLT or a GDU. In addition, it can run on a standard PC using a special version of the GDU or BPLT software. In all cases, a suitable ARINC-429 interface must be present.