Decommutation of Mil-Std 1553B Data from EA6B or IRIG Telemetry Formats

Abstract

With the acceptance of Mil-Std-1553B by vehicle and weapons industries a wealth of new information is available for vehicle testing. In the past, selected data was extracted and included in a standard PCM telemetry stream. But only the selected data was made available. In EA6B and in the proposed IRIG Standard, multiple Mil-Std-1553B data busses are combined with identifying control bits in a single PCM telemetry stream. All of the information traveling each bus is available to the ground station. These formats share a number of features. One is that for each Bus the Mil-Std-1553B word appears in the same order in the telemetry stream. Another is that individual data words do not depend on their position in the telemetry stream for identification, but they do depend on the control information associated with the current message to give meaning to the data words. An efficient approach is outlined for identifying, selecting and routing individual measurements, messages, and/or all Mil-Std-1553B bus information to processes and I/O devices in a data flow environment.