A match circuit connected to a bus carrying data is described. The system generates a first and second data field of symbols, then encodes them to produce complex conjugates of the respective symbols. By detecting combinations of signals on one or more of the data signal line, clock signal line and select signal line, the SPI controller can detect the initiation of data read and write operations that may be in accordance with any of several different SPI protocols. Alternatively, only the eNB inspects the packets. As a result, examinations carried out in accordance with the present invention can advantageously be relatively noninvasive, and the subject being examined need not even be aware of the examination. According to the method, most aspects of the legacy HFC CATV system may be retained, however at the CATV head end, the optical fiber transmitter system is replaced by an improved system that extracts the underlying symbols from legacy waveforms, packages these symbols into optical fiber optimized packets, and transmits downstream.