Both the PosApp (SimGEN / SimREPLAYplus / SimREPLAY) and SimPLEX software applications allow output of NMEA messages over the COM port in the PC. However, the timing of the NMEA message output, with respect to the simulator 1PPS (GPS time), is subtly different between the two applications as a result of the way in which they process the scenario data during the test.
Of course the chosen RS232 baud rate will also influence the reception time for the message.
This may be of primary concern to customers upgrading their products from SimPLEX capability to PosApp capability, e.g. from an STR4500 to a GSS6700, and have chosen to use the timing of NMEA messages to synchronise their UUT. Some small realignment of their test set-up may be required, or direct use of the simulator 1PPS output may be preferable.